<SEC-DOCUMENT>0001798849-22-000020.txt : 20220209
<SEC-HEADER>0001798849-22-000020.hdr.sgml : 20220209
<ACCEPTANCE-DATETIME>20220209142808
ACCESSION NUMBER:		0001798849-22-000020
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220207
FILED AS OF DATE:		20220209
DATE AS OF CHANGE:		20220209

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Durable Capital Partners LP
		CENTRAL INDEX KEY:			0001798849
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40653
		FILM NUMBER:		22605870

	BUSINESS ADDRESS:	
		STREET 1:		5425 WISCONSIN AVENUE
		STREET 2:		SUITE #802
		CITY:			CHEVY CHASE
		STATE:			MD
		ZIP:			20815
		BUSINESS PHONE:		301-690-9567

	MAIL ADDRESS:	
		STREET 1:		5425 WISCONSIN AVENUE
		STREET 2:		SUITE #802
		CITY:			CHEVY CHASE
		STATE:			MD
		ZIP:			20815

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Duolingo, Inc.
		CENTRAL INDEX KEY:			0001562088
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				453055872
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5900 PENN AVE, SECOND FLOOR
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15206
		BUSINESS PHONE:		(412) 347-6116

	MAIL ADDRESS:	
		STREET 1:		5900 PENN AVE, SECOND FLOOR
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15206
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2022-02-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001562088</issuerCik>
        <issuerName>Duolingo, Inc.</issuerName>
        <issuerTradingSymbol>DUOL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001798849</rptOwnerCik>
            <rptOwnerName>Durable Capital Partners LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5425 WISCONSIN AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE #802</rptOwnerStreet2>
            <rptOwnerCity>CHEVY CHASE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20815</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-02-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1020</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>90.8</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2903255</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote 1</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities are held directly by Durable Capital Master Fund LP (&quot;Durable Capital Master Fund&quot;). Durable Capital Partners LP (&quot;Durable Capital&quot;) acts as the investment adviser to Durable Capital Master Fund and has sole voting power and sole investment power over the securities reported on this Form 4. Durable Capital Partners GP LLC (&quot;Durable GP&quot;) is the general partner of Durable Capital, and Henry Ellenbogen is the chief investment officer of Durable Capital and the managing member of Durable GP. Each of Durable Capital Master Fund, Durable Capital, Durable GP and Mr. Ellenbogen disclaim beneficial ownership of the reported securities, except to the extent of any pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Durable Capital Partners LP, By: Julie Jack, its Authorized Person</signatureName>
        <signatureDate>2022-02-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
