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            <filer>
                <filerCredentials>
                    <cik>0001788251</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001561550</issuerCik>
            <issuerName>DATADOG INC </issuerName>
            <secFileNumber>001-39051</secFileNumber>
            <issuerAddress>
                <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                <ns2:city>NEW YORK </ns2:city>
                <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                <ns2:zipCode>10018</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>8663294466</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Armelle DeMadre</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>38th Fl.</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>3750</noOfUnitsSold>
            <aggregateMarketValue>368925.00</aggregateMarketValue>
            <noOfUnitsOutstanding>296268680</noOfUnitsOutstanding>
            <approxSaleDate>07/03/2023</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>07/03/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>3750</amountOfSecuritiesAcquired>
            <paymentDate>07/03/2023</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/05/2023</saleDate>
            <amountOfSecuritiesSold>2080</amountOfSecuritiesSold>
            <grossProceeds>208538.51</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/02/2023</saleDate>
            <amountOfSecuritiesSold>19897</amountOfSecuritiesSold>
            <grossProceeds>1989700.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/02/2023</saleDate>
            <amountOfSecuritiesSold>4014</amountOfSecuritiesSold>
            <grossProceeds>402732.65</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/01/2023</saleDate>
            <amountOfSecuritiesSold>1875</amountOfSecuritiesSold>
            <grossProceeds>174375.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/01/2023</saleDate>
            <amountOfSecuritiesSold>4043</amountOfSecuritiesSold>
            <grossProceeds>383721.13</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE</name>
                <address>
                    <ns2:street1>620 EIGHTH AVENUE, 45TH FLOOR </ns2:street1>
                    <ns2:city>NEW YORK </ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10018</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/17/2023</saleDate>
            <amountOfSecuritiesSold>6543</amountOfSecuritiesSold>
            <grossProceeds>588870.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>Securities to be sold were registered on Form S-8</remarks>
        <noticeSignature>
            <noticeDate>07/03/2023</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>09/09/2022</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Armelle de Madre</signature>
        </noticeSignature>
    </formData>
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144
0001788251
XXXXXXXX
LIVE
0001561550
DATADOG INC
001-39051
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
8663294466
Armelle DeMadre
Officer
COMMON
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
38th Fl.
New York
NY
10004
3750
368925.00
296268680
07/03/2023
NASDAQ
Common
07/03/2023
Exercise of Stock Options
Issuer
N
3750
07/03/2023
Cash
N
10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
06/05/2023
2080
208538.51
10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
06/02/2023
19897
1989700.00
ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
06/02/2023
4014
402732.65
10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
06/01/2023
1875
174375.00
ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
06/01/2023
4043
383721.13
10b5-1 Sales Plan for ARMELLE BEATRICECAROLETIELEMAN DE MADRE
620 EIGHTH AVENUE, 45TH FLOOR
NEW YORK
NY
10018
Common
05/17/2023
6543
588870.00
Securities to be sold were registered on Form S-8
07/03/2023
09/09/2022
/s/ Armelle de Madre