<SEC-DOCUMENT>0001562180-23-000307.txt : 20230109
<SEC-HEADER>0001562180-23-000307.hdr.sgml : 20230109
<ACCEPTANCE-DATETIME>20230109182743
ACCESSION NUMBER:		0001562180-23-000307
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230105
FILED AS OF DATE:		20230109
DATE AS OF CHANGE:		20230109

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Whitehurst James M
		CENTRAL INDEX KEY:			0001292272

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40817
		FILM NUMBER:		23519249

	MAIL ADDRESS:	
		STREET 1:		IBM CORPORATION
		STREET 2:		ONE NEW ORCHARD RD
		CITY:			ARMONK
		STATE:			NY
		ZIP:			10504-1722

	FORMER NAME:	
		FORMER CONFORMED NAME:	Whitehurst James Moon
		DATE OF NAME CHANGE:	20210415

	FORMER NAME:	
		FORMER CONFORMED NAME:	Whitehurst James M
		DATE OF NAME CHANGE:	20040528

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Amplitude, Inc.
		CENTRAL INDEX KEY:			0001866692
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		201 THIRD STREET, SUITE 200
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94103
		BUSINESS PHONE:		510 473-5668

	MAIL ADDRESS:	
		STREET 1:		201 THIRD STREET, SUITE 200
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94103
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primarydocument.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-01-05</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0001866692</issuerCik>
        <issuerName>Amplitude, Inc.</issuerName>
        <issuerTradingSymbol>AMPL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001292272</rptOwnerCik>
            <rptOwnerName>Whitehurst James M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AMPLITUDE, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>201 THIRD ST., SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>false</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-01-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1157.00</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>128544.00</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock units (&quot;RSUs&quot;) that were granted pursuant to the Issuer's Non-Employee Director Compensation Program (the &quot;Program&quot;) in lieu of retainer fees. Each RSU represents a right to receive one share of Class A Common Stock, with settlement to take place either (i) on a date selected by the reporting person pursuant to the Program or (ii) as otherwise provided by the Program.</footnote>
        <footnote id="F2">Includes 89,482 RSUs.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Elizabeth Fisher, as attorney in fact for James M. Whitehurst</signatureName>
        <signatureDate>2023-01-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
