<?xml version="1.0" encoding="US-ASCII"?>
<!-- DFIN New ActiveDisclosure (SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date :2022-02-16T14:35:51.3602+00:00 -->
<!-- Copyright (c) 2022 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
<xsd:schema targetNamespace="http://www.amplitude.com/20211231" attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:country="http://xbrl.sec.gov/country/2021" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2020-01-21" xmlns:enum2="http://xbrl.org/2020/extensible-enumerations-2.0" xmlns:srt="http://fasb.org/srt/2021-01-31" xmlns:ampl="http://www.amplitude.com/20211231" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:us-gaap="http://fasb.org/us-gaap/2021-01-31" xmlns:dei="http://xbrl.sec.gov/dei/2021q4" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink">
  <xsd:import schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" namespace="http://www.xbrl.org/2003/instance"/>
  <xsd:import schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" namespace="http://www.xbrl.org/2003/linkbase"/>
  <xsd:import schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" namespace="http://xbrl.org/2005/xbrldt"/>
  <xsd:import schemaLocation="https://xbrl.sec.gov/country/2021/country-2021.xsd" namespace="http://xbrl.sec.gov/country/2021"/>
  <xsd:import schemaLocation="https://xbrl.fasb.org/srt/2021/elts/srt-2021-01-31.xsd" namespace="http://fasb.org/srt/2021-01-31"/>
  <xsd:import schemaLocation="https://www.xbrl.org/2020/extensible-enumerations-2.0.xsd" namespace="http://xbrl.org/2020/extensible-enumerations-2.0"/>
  <xsd:import schemaLocation="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd" namespace="http://fasb.org/us-gaap/2021-01-31"/>
  <xsd:import schemaLocation="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd" namespace="http://xbrl.sec.gov/dei/2021q4"/>
  <xsd:import schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd" namespace="http://www.xbrl.org/dtr/type/2020-01-21"/>
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ampl-20211231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:title="Labels link" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ampl-20211231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:title="Presentation link" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ampl-20211231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:title="Definition link" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ampl-20211231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:title="Calculation link" xlink:type="simple"/>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DocumentDocumentAndEntityInformation" id="Role_DocumentDocumentAndEntityInformation">
        <link:definition>100000 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheets" id="Role_StatementCondensedConsolidatedBalanceSheets">
        <link:definition>100010 - Statement - Condensed Consolidated Balance Sheets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheetsParenthetical" id="Role_StatementCondensedConsolidatedBalanceSheetsParenthetical">
        <link:definition>100020 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfOperations" id="Role_StatementCondensedConsolidatedStatementsOfOperations">
        <link:definition>100030 - Statement - Condensed Consolidated Statements of Operations</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfRedeemableConvertiblePreferredStockAndStockholdersEquityDeficit" id="Role_StatementCondensedConsolidatedStatementsOfRedeemableConvertiblePreferredStockAndStockholdersEquityDeficit">
        <link:definition>100040 - Statement - Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfRedeemableConvertiblePreferredStockAndStockholdersEquityDeficitParenthetical" id="Role_StatementCondensedConsolidatedStatementsOfRedeemableConvertiblePreferredStockAndStockholdersEquityDeficitParenthetical">
        <link:definition>100050 - Statement - Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited" id="StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited">
        <link:definition>100060 - Statement - Condensed Consolidated Statements of Cash Flows (unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureSummaryOfBusinessAndSignificantAccountingPolicies" id="Role_DisclosureSummaryOfBusinessAndSignificantAccountingPolicies">
        <link:definition>100070 - Disclosure - Summary of Business and Significant Accounting Policies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureRevenueFromContractsWithCustomers" id="DisclosureRevenueFromContractsWithCustomers">
        <link:definition>100080 - Disclosure - Revenue from Contracts with Customers</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureBalanceSheetComponents" id="Role_DisclosureBalanceSheetComponents">
        <link:definition>100090 - Disclosure - Balance Sheet Components</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureAcquisitionIntangibleAssetsAndGoodwill1" id="DisclosureAcquisitionIntangibleAssetsAndGoodwill1">
        <link:definition>100100 - Disclosure - Acquisition, Intangible Assets, and Goodwill</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureRedeemableConvertiblePreferredStock" id="Role_DisclosureRedeemableConvertiblePreferredStock">
        <link:definition>100110 - Disclosure - Redeemable Convertible Preferred Stock</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlans" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlans">
        <link:definition>100120 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureDebt" id="Role_DisclosureDebt">
        <link:definition>100130 - Disclosure - Debt</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureEmployeeBenefitPlans" id="Role_DisclosureEmployeeBenefitPlans">
        <link:definition>100140 - Disclosure - Employee Benefit Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureIncomeTaxes" id="Role_DisclosureIncomeTaxes">
        <link:definition>100150 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureCommitmentsAndContingencies" id="Role_DisclosureCommitmentsAndContingencies">
        <link:definition>100160 - Disclosure - Commitments and Contingencies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureNetLossPerShare" id="Role_DisclosureNetLossPerShare">
        <link:definition>100170 - Disclosure - Net Loss Per Share</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureSubsequentEvents" id="Role_DisclosureSubsequentEvents">
        <link:definition>100180 - Disclosure - Subsequent Events</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesPolicies" id="Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesPolicies">
        <link:definition>100190 - Disclosure - Summary of Business and Significant Accounting Policies (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesTables" id="DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesTables">
        <link:definition>100200 - Disclosure - Summary of Business and Significant Accounting Policies (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureBalanceSheetComponentsTables" id="Role_DisclosureBalanceSheetComponentsTables">
        <link:definition>100210 - Disclosure - Balance Sheet Components (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillTables" id="Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillTables">
        <link:definition>100220 - Disclosure - Acquisition Intangible Assets and Goodwill (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureRedeemableConvertiblePreferredStockTables" id="Role_DisclosureRedeemableConvertiblePreferredStockTables">
        <link:definition>100230 - Disclosure - Redeemable Convertible Preferred Stock (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansTables" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansTables">
        <link:definition>100240 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesTable" id="Role_DisclosureCommitmentsAndContingenciesTable">
        <link:definition>100250 - Disclosure - Commitments and Contingencies (Table)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesTables" id="DisclosureIncomeTaxesTables">
        <link:definition>100260 - Disclosure - Income Taxes (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureNetLossPerShareTables" id="Role_DisclosureNetLossPerShareTables">
        <link:definition>100270 - Disclosure - Net Loss Per Share (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesAdditionalInformationDetails" id="Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesAdditionalInformationDetails">
        <link:definition>100280 - Disclosure - Summary of Business and Significant Accounting Policies - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSummaryOfBusinessAndSignificantAccountingPoliciessummaryOfRemainingPerformanceObligationsDetails" id="DisclosureSummaryOfBusinessAndSignificantAccountingPoliciessummaryOfRemainingPerformanceObligationsDetails">
        <link:definition>100290 - Disclosure - Summary of Business and Significant Accounting Policies-Summary of Remaining Performance Obligations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetails" id="DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetails">
        <link:definition>100300 - Disclosure - Revenue from Contracts with Customers (Additional Information) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesSummaryOfDisaggregationOfRevenueByGeographicAreasDetails" id="DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesSummaryOfDisaggregationOfRevenueByGeographicAreasDetails">
        <link:definition>100310 - Disclosure - Summary of Business and Significant Accounting Policies - Summary of Disaggregation of Revenue by Geographic Areas (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesSummaryOfDeferredCommissionsDetails" id="DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesSummaryOfDeferredCommissionsDetails">
        <link:definition>100320 - Disclosure - Summary of Business and Significant Accounting Policies - Summary of Deferred Commissions (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesScheduleOfCashCashEquivalentsAndRestrictedCashDetails" id="DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesScheduleOfCashCashEquivalentsAndRestrictedCashDetails">
        <link:definition>100330 - Disclosure - Summary of Business and Significant Accounting Policies - Schedule of Cash, Cash Equivalents and Restricted Cash (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesScheduleOfEstimatedUsefulLivesOfPropertyAndEquipmentDetails" id="Role_DisclosureSummaryOfBusinessAndSignificantAccountingPoliciesScheduleOfEstimatedUsefulLivesOfPropertyAndEquipmentDetails">
        <link:definition>100340 - Disclosure - Summary of Business and Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureBalanceSheetComponentsScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails" id="Role_DisclosureBalanceSheetComponentsScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails">
        <link:definition>100350 - Disclosure - Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureBalanceSheetComponentsScheduleOfPropertyAndEquipmentNetDetails" id="DisclosureBalanceSheetComponentsScheduleOfPropertyAndEquipmentNetDetails">
        <link:definition>100360 - Disclosure - Balance Sheet Components - Schedule of Property and Equipment, Net (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureBalanceSheetComponentsScheduleOfCarryingValueOfCapitalizedInternalCostDetails" id="DisclosureBalanceSheetComponentsScheduleOfCarryingValueOfCapitalizedInternalCostDetails">
        <link:definition>100370 - Disclosure - Balance Sheet Components - Schedule Of Carrying value Of Capitalized Internal Cost (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureBalanceSheetComponentsScheduleOfAccruedExpensesDetails" id="Role_DisclosureBalanceSheetComponentsScheduleOfAccruedExpensesDetails">
        <link:definition>100380 - Disclosure - Balance Sheet Components - Schedule of Accrued Expenses (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureBalanceSheetComponentsAdditionalInformationDetails" id="DisclosureBalanceSheetComponentsAdditionalInformationDetails">
        <link:definition>100390 - Disclosure - Balance Sheet Components - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillAdditionalInformationDetails" id="Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillAdditionalInformationDetails">
        <link:definition>100400 - Disclosure - Acquisition Intangible Assets and Goodwill - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillScheduleOfIntangibleAssetsNetDetails" id="Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillScheduleOfIntangibleAssetsNetDetails">
        <link:definition>100410 - Disclosure - Acquisition Intangible Assets and Goodwill - Schedule of Intangible Assets, Net (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillScheduleOfExpectedFutureAmortizationExpenseDetails" id="Role_DisclosureAcquisitionIntangibleAssetsAndGoodwillScheduleOfExpectedFutureAmortizationExpenseDetails">
        <link:definition>100420 - Disclosure - Acquisition Intangible Assets and Goodwill - Schedule of Expected Future Amortization Expense (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureRedeemableConvertiblePreferredStockAdditionalInformationDetails" id="Role_DisclosureRedeemableConvertiblePreferredStockAdditionalInformationDetails">
        <link:definition>100430 - Disclosure - Redeemable Convertible Preferred Stock - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureRedeemableConvertiblePreferredStockScheduleOfConvertiblePreferredStockDetails" id="Role_DisclosureRedeemableConvertiblePreferredStockScheduleOfConvertiblePreferredStockDetails">
        <link:definition>100440 - Disclosure - Redeemable Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureRedeemableConvertiblePreferredStockScheduleOfConvertiblePreferredStockParentheticalDetails" id="Role_DisclosureRedeemableConvertiblePreferredStockScheduleOfConvertiblePreferredStockParentheticalDetails">
        <link:definition>100450 - Disclosure - Redeemable Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Parenthetical) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansPreferredAndCommonStockAdditionalInformationDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansPreferredAndCommonStockAdditionalInformationDetails">
        <link:definition>100460 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Preferred and Common Stock - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfReservedSharesOfCommonStockDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfReservedSharesOfCommonStockDetails">
        <link:definition>100470 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Schedule of Reserved Shares of Common Stock (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansAdditionalInformationDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansAdditionalInformationDetails">
        <link:definition>100480 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansSummaryOfStockOptionActivityDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansSummaryOfStockOptionActivityDetails">
        <link:definition>100490 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Summary of Stock Option Activity (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfAssumptionsAndDataInputsToEstimateFairValueOfOptionsDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfAssumptionsAndDataInputsToEstimateFairValueOfOptionsDetails">
        <link:definition>100500 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Schedule of Assumptions and Data Inputs to Estimate Fair Value of Options (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfRsuActivityDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfRsuActivityDetails">
        <link:definition>100510 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Schedule of RSU Activity (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersDeficitAndEquityIncentivePlansFairValueOfSharesToBeGrantedUnderTheEsppUtilizingTheBlackscholesOptionpricingModelDe" id="DisclosureStockholdersDeficitAndEquityIncentivePlansFairValueOfSharesToBeGrantedUnderTheEsppUtilizingTheBlackscholesOptionpricingModelDe">
        <link:definition>100520 - Disclosure - Stockholders' (Deficit) and Equity Incentive Plans - fair value of shares to be granted under the ESPP utilizing the Black-Scholes option-pricing model (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfStockBasedCompensationExpensesDetails" id="DisclosureStockholdersEquityDeficitAndEquityIncentivePlansScheduleOfStockBasedCompensationExpensesDetails">
        <link:definition>100530 - Disclosure - Stockholders' Equity (Deficit) and Equity Incentive Plans - Schedule of Stock Based Compensation Expenses (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetails" id="Role_DisclosureDebtAdditionalInformationDetails">
        <link:definition>100540 - Disclosure - Debt - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetails" id="Role_DisclosureIncomeTaxesAdditionalInformationDetails">
        <link:definition>100550 - Disclosure - Income Taxes - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesScheduleOfPretaxBookLossDetails" id="DisclosureIncomeTaxesScheduleOfPretaxBookLossDetails">
        <link:definition>100560 - Disclosure - Income Taxes - Schedule of Pre-Tax Book Loss (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesScheduleOfIncomeTaxProvisionsDetails" id="DisclosureIncomeTaxesScheduleOfIncomeTaxProvisionsDetails">
        <link:definition>100570 - Disclosure - Income Taxes - Schedule of Income Tax Provisions (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesScheduleOfReconciliationOfIncomeTaxProvisionToFederalIncomeTaxRateDetails" id="DisclosureIncomeTaxesScheduleOfReconciliationOfIncomeTaxProvisionToFederalIncomeTaxRateDetails">
        <link:definition>100580 - Disclosure - Income Taxes - Schedule of Reconciliation of Income Tax Provision to Federal Income Tax Rate (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesScheduleOfDeferredIncomeTaxAssetsAndLiabilitiesDetails" id="DisclosureIncomeTaxesScheduleOfDeferredIncomeTaxAssetsAndLiabilitiesDetails">
        <link:definition>100590 - Disclosure - Income Taxes - Schedule of Deferred Income Tax Assets and Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureIncomeTaxesSummaryOfReconciliationOfUnrecognizedTaxBenefitDetails" id="DisclosureIncomeTaxesSummaryOfReconciliationOfUnrecognizedTaxBenefitDetails">
        <link:definition>100600 - Disclosure - Income Taxes - Summary of Reconciliation of Unrecognized Tax Benefit (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFutureMinimumLeasePaymentsDetails" id="Role_DisclosureCommitmentsAndContingenciesFutureMinimumLeasePaymentsDetails">
        <link:definition>100610 - Disclosure - Commitments and Contingencies - Future Minimum Lease Payments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetails" id="Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetails">
        <link:definition>100620 - Disclosure - Commitments and Contingencies - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfBasicAndDilutedNetLossPerShareDetails" id="Role_DisclosureNetLossPerShareScheduleOfBasicAndDilutedNetLossPerShareDetails">
        <link:definition>100630 - Disclosure - Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntDilutiveSecuritiesExcludedFromCalculationOfDilutedNetLossPerShareDetails" id="Role_DisclosureNetLossPerShareScheduleOfAntDilutiveSecuritiesExcludedFromCalculationOfDilutedNetLossPerShareDetails">
        <link:definition>100640 - Disclosure - Net Loss Per Share - Schedule of Ant-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.amplitude.com/20211231/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetails" id="DisclosureSubsequentEventsAdditionalInformationDetails">
        <link:definition>100650 - Disclosure - Subsequent Events - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element id="ampl_AcquisitionsIntangibleAssetsAndGoodwillDisclosureAbstract" name="AcquisitionsIntangibleAssetsAndGoodwillDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_RedeemableConvertiblePreferredStockAbstract" name="RedeemableConvertiblePreferredStockAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_AccruedLiabilityFromEarlyExercisedStockOptionsCurrent" name="AccruedLiabilityFromEarlyExercisedStockOptionsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_AccruedSalesTaxCurrent" name="AccruedSalesTaxCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_AdditionsToDeferredCommissions" name="AdditionsToDeferredCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_AdjustmentsToAdditionalPaidInCapitalVestingOfEarlyExercisedStockOptions" name="AdjustmentsToAdditionalPaidInCapitalVestingOfEarlyExercisedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_AmortizationOfDeferredCommissions" name="AmortizationOfDeferredCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingShares" name="ConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingValue" name="ConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_DeferredCommission" name="DeferredCommission" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_DeferredCommissionAmortizationPeriod" name="DeferredCommissionAmortizationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DeferredCommissionCurrent" name="DeferredCommissionCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_DeferredCommissionCurrentAndNoncurrent" name="DeferredCommissionCurrentAndNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_DeferredCommissionNoncurrent" name="DeferredCommissionNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_DeferredTaxAssetFixedAssets" name="DeferredTaxAssetFixedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_DeferredTaxLiabilitiesDeferredCommissionCosts" name="DeferredTaxLiabilitiesDeferredCommissionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_DeferredTaxLiabilitiesFixedAssets" name="DeferredTaxLiabilitiesFixedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_EffectiveIncomeTaxRateReconciliationPermanentDifferences" name="EffectiveIncomeTaxRateReconciliationPermanentDifferences" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_EmployeeStockPurchasePlanWithholding" name="EmployeeStockPurchasePlanWithholding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_EquityIncentiveAwardTerm" name="EquityIncentiveAwardTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_FairValueOfBusinessConsideration" name="FairValueOfBusinessConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ImpairmentLossOnLongLivedAsset" name="ImpairmentLossOnLongLivedAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_IncreaseDecreaseInDeferredCommissions" name="IncreaseDecreaseInDeferredCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_IncreaseDecreaseInNoncurrentLiabilities" name="IncreaseDecreaseInNoncurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_LiabilityRelatedToEarlyExercisedShares" name="LiabilityRelatedToEarlyExercisedShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_NetIssuanceCostsOfRedeemableConvertiblePreferredStock" name="NetIssuanceCostsOfRedeemableConvertiblePreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_NetOperatingLossCarryforwardExpirationYear" name="NetOperatingLossCarryforwardExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_NetOperatingLossCarryforwardsAvailableToOffsetFutureTaxableIncome" name="NetOperatingLossCarryforwardsAvailableToOffsetFutureTaxableIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_NumberOfDividendOrDistributionToBePaidOnSharesOfCommonStock" name="NumberOfDividendOrDistributionToBePaidOnSharesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ampl_NumberOfDividendsDeclared" name="NumberOfDividendsDeclared" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ampl_OtherPrepaidExpensesAndOtherAssetsCurrent" name="OtherPrepaidExpensesAndOtherAssetsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_PaymentsForRepurchaseOfUnvestedStockOptions" name="PaymentsForRepurchaseOfUnvestedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_PrepaidHostingCurrent" name="PrepaidHostingCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_PropertyPlantAndEquipmentDepreciationAndAmortization" name="PropertyPlantAndEquipmentDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_RegistrationStatementAggregateProceeds" name="RegistrationStatementAggregateProceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_RestrictedStockSharesIssuedUnderEmployeeRetention" name="RestrictedStockSharesIssuedUnderEmployeeRetention" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ShareBasedCompensationArrangementByPerformanceAwardsExpense" name="ShareBasedCompensationArrangementByPerformanceAwardsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodTotalIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodTotalIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsIssuedGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsIssuedGrantDateFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_ShareBasedCompensationWeightedAverageRemainingVestingPeriod" name="ShareBasedCompensationWeightedAverageRemainingVestingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_StockIssuedDuringPeriodSharesDonationOfCommonStockAndRepurchaseOfUnvestedStockOptions" name="StockIssuedDuringPeriodSharesDonationOfCommonStockAndRepurchaseOfUnvestedStockOptions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_StockIssuedDuringPeriodSharesVestingOfRestrictedStockUnits" name="StockIssuedDuringPeriodSharesVestingOfRestrictedStockUnits" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_StockIssuedDuringPeriodValueDonationOfCommonStockAndRepurchaseOfUnvestedStockOptions" name="StockIssuedDuringPeriodValueDonationOfCommonStockAndRepurchaseOfUnvestedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_StockIssuedDuringPeriodValueVestingOfRestrictedStockUnits" name="StockIssuedDuringPeriodValueVestingOfRestrictedStockUnits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_StockOptionPlanTerm" name="StockOptionPlanTerm" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_StockVestingPeriod" name="StockVestingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingShares" name="TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingValue" name="TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponDirectListingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_UnrecognizedShareBasedCompensationExpenses" name="UnrecognizedShareBasedCompensationExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ampl_VestingOfEarlyExercisedOptions" name="VestingOfEarlyExercisedOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ampl_APACMember" name="APACMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_ClassAAndClassBCommonStockMember" name="ClassAAndClassBCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_DevelopedTechnologyMember" name="DevelopedTechnologyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_DirectListingMember" name="DirectListingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_EquityPlanStockOptionsEarlyExercisedMember" name="EquityPlanStockOptionsEarlyExercisedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_EquityPlanStockOptionsOutstandingMember" name="EquityPlanStockOptionsOutstandingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_InternalUseSoftwareMember" name="InternalUseSoftwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_InternationalMember" name="InternationalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_NoCustomerMember" name="NoCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_NonPlanStockOptionsMember" name="NonPlanStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_OneCustomerMember" name="OneCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_OptionAndGrantPlanMember" name="OptionAndGrantPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_PrivatelyHeldCompanyMember" name="PrivatelyHeldCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_RestrictedStockUnitsOutstandingMember" name="RestrictedStockUnitsOutstandingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_RSUsMember" name="RSUsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SecondaryTransactionsMember" name="SecondaryTransactionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SeriesARedeemableConvertiblePreferredStockMember" name="SeriesARedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SeriesDRedeemableConvertiblePreferredStockMember" name="SeriesDRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SeriesERedeemableConvertiblePreferredStockMember" name="SeriesERedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SeriesFRedeemableConvertiblePreferredStockMember" name="SeriesFRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SharesIssuablePursuantToThe2021EmployeeStockPurchasePlanMember" name="SharesIssuablePursuantToThe2021EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_SoftwareMember" name="SoftwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_TwoCustomerMember" name="TwoCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_TwoExecutivesMember" name="TwoExecutivesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_TwoThousandFourteenStockOptionPlanMember" name="TwoThousandFourteenStockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_TwoThousandsTwentyOneEmployeeStockPurchasePlanMember" name="TwoThousandsTwentyOneEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_TwoThousandsTwentyOneIncentiveAwardPlanMember" name="TwoThousandsTwentyOneIncentiveAwardPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_WarrantsMember" name="WarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ampl_ConcentrationOfRiskAndSignificantCustomersPolicyTextBlock" name="ConcentrationOfRiskAndSignificantCustomersPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DeferredCommissionsPolicyTextBlock" name="DeferredCommissionsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DeferredRevenuePolicyTextBlock" name="DeferredRevenuePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DescriptionOfBusinessPolicyTextBlock" name="DescriptionOfBusinessPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DisaggregationOfRevenuePolicyTextBlock" name="DisaggregationOfRevenuePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ReclassificationPolicyTextBlock" name="ReclassificationPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_RedeemableConvertiblePreferredStockTableTextBlock" name="RedeemableConvertiblePreferredStockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ScheduleOfDeferredCommissionsTableTextBlock" name="ScheduleOfDeferredCommissionsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ScheduleOfReservedSharesOfCommonStockTableTextBlock" name="ScheduleOfReservedSharesOfCommonStockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_BusinessCombinationIntangibleAssetsAndGoodwillDisclosureTextBlock" name="BusinessCombinationIntangibleAssetsAndGoodwillDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_DirectListingPolicyTextBlock" name="DirectListingPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_RedeemableConvertiblePreferredStockTextBlock" name="RedeemableConvertiblePreferredStockTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_RisksAndUncertaintiesPolicyTextBlock" name="RisksAndUncertaintiesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ScheduleOfConvertiblePreferredStockTableTextBlock" name="ScheduleOfConvertiblePreferredStockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ampl_ScheduleOfPropertyAndEqupmentUsefulLifeTableTextBlock" name="ScheduleOfPropertyAndEqupmentUsefulLifeTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
