<SEC-DOCUMENT>0001306830-25-000241.txt : 20251119
<SEC-HEADER>0001306830-25-000241.hdr.sgml : 20251119
<ACCEPTANCE-DATETIME>20251119164149
ACCESSION NUMBER:		0001306830-25-000241
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251117
FILED AS OF DATE:		20251119
DATE AS OF CHANGE:		20251119

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			McGilvray Aaron M
		CENTRAL INDEX KEY:			0001917582
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32410
		FILM NUMBER:		251499867

	MAIL ADDRESS:	
		STREET 1:		222 W. LAS COLINAS BLVD
		STREET 2:		SUITE 900N
		CITY:			IRVING
		STATE:			TX
		ZIP:			75039

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Celanese Corp
		CENTRAL INDEX KEY:			0001306830
		STANDARD INDUSTRIAL CLASSIFICATION:	PLASTIC MATERIAL, SYNTH RESIN/RUBBER, CELLULOS (NO GLASS) [2820]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				980420726
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		222 W. LAS COLINAS BLVD., SUITE 900N
		CITY:			IRVING
		STATE:			TX
		ZIP:			75039-5421
		BUSINESS PHONE:		972-443-4000

	MAIL ADDRESS:	
		STREET 1:		222 W. LAS COLINAS BLVD., SUITE 900N
		CITY:			IRVING
		STATE:			TX
		ZIP:			75039-5421

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Celanese CORP
		DATE OF NAME CHANGE:	20041102

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Blackstone Crystal Holdings Capital Partners (Cayman) IV Ltd.
		DATE OF NAME CHANGE:	20041022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1763588506.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-11-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001306830</issuerCik>
        <issuerName>Celanese Corp</issuerName>
        <issuerTradingSymbol>CE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001917582</rptOwnerCik>
            <rptOwnerName>McGilvray Aaron M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>222 W LAS COLINAS BLVD SUITE 900N</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>IRVING</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75039</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Accounting Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-11-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2980</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10319.378</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>798.8018</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Time-based restricted stock units (&quot;RSUs&quot;) granted pursuant to the Company's Amended and Restated 2018 Global Incentive Plan. Each RSU represents the right to receive one share of Common Stock. The RSUs will vest, subject to continued employment, with respect to 50% of the RSUs on each of November 17, 2026 and November 17, 2027.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Adam R. Santosuosso, Attorney-in-Fact for Aaron M. McGilvray</signatureName>
        <signatureDate>2025-11-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
