July 10, 2019

Olivier Pomel
Chief Executive Officer
Datadog, Inc.
620 8th Avenue, 45th Floor
New York, NY 10018

       Re: Datadog, Inc.
           Draft Registration Statement on Form S-1
           Submitted June 13, 2019
           CIK No. 0001561550

Dear Mr. Pomel:

       We have reviewed your draft registration statement and have the
following comments. In
some of our comments, we may ask you to provide us with information so we may
better
understand your disclosure.

       Please respond to this letter by providing the requested information and
either submitting
an amended draft registration statement or publicly filing your registration
statement on
EDGAR. If you do not believe our comments apply to your facts and circumstances
or do not
believe an amendment is appropriate, please tell us why in your response.

      After reviewing the information you provide in response to these comments
and your
amended draft registration statement or filed registration statement, we may
have additional
comments.

Draft Registration Statement on Form S-1

Management Discussion and Analysis of Financial Condition and Results of
Operations
Overview, page 55

1.     Please clarify whether users of your free trials or free tiers of your
platform are included
       in your customer count. If so, revise to also disclose the number of
paid customers. In
       addition, please disclose the actual number of customers and the number
of customers
       with annual recurring revenue greater than $100,000 for each period
presented, including
       December 31, 2018, rather than referring to a count in excess of a
certain amount.
 Olivier Pomel
FirstName LastNameOlivier Pomel
Datadog, Inc.
Comapany NameDatadog, Inc.
July 10, 2019
July 10, 2019 Page 2
Page 2
FirstName LastName
Factors Affecting Our Performance, page 57

2.       You state that annualized revenue run-rate is calculated by taking the
monthly recurring
         revenue (MRR), which includes committed amounts as well any additional
usage, and
         multiplying it by 12. Please tell us how you determined that
additional usage in a given
         month is recurring. Also, clarify whether monthly subscription
customers are included in
         MRR and if so, explain your basis for annualizing revenue derived from
such customers.
          In your response, please tell us the amount of revenue recognized
from monthly
         subscriptions for each period presented.
3.       You use "ARR" to describe both "Annual Recurring Revenue" and
"Annualized Revenue
         Run-rate." Please revise to clarify whether these both represent the
same metric. If
         not, use another acronym for one of these metrics and explain how you
calculate annual
         recurring revenue.
4.       Please revise to provide comparative disclosure of your actual
dollar-based net retention
         rate for each reported period and discuss any significant fluctuations
in such rates.
Liquidity and Capital Resources, page 65

5.       Please provide a brief description of the operating lease and purchase
commitments listed
         in your Contractual Obligations and Commitments table. Please also
advise us whether
         any office space leases, such as for your New York City headquarters,
are material
         agreements upon which you are substantially dependent pursuant to Item
601(b)(10) of
         Regulation S-K.
6.       Please provide a description of the hosting agreement that you entered
into in April 2019
         in which you committed to spend at least $225 million over the next
three years. Your
         description should include material terms and the identity of the data
center services
         provider.
Business
Our Platform, page 82

7.       You disclose that you "fully support and maintain all of our
integrations." You further
         indicate that alternatives to your platform require significant
professional services. Please
         clarify how your clients integrate your platform into their systems
and specifically address
         whether they use their own internal IT staff, resellers or other
third-parties, or your
         support and maintenance staff.
Sales and Marketing, page 86

8.       You briefly describe sales channels including resellers, distributors,
managed service
         providers and cloud provider marketplaces. Please clarify whether you
derive a material
         amount of revenue from these non-direct sales channels.
 Olivier Pomel
Datadog, Inc.
July 10, 2019
Page 3
9.       Clarify whether any organization accounted for 10% or more of your
revenue for the
         fiscal years ended March 31, 2017 and 2018. In this regard, you state
that in some cases,
         a single organization may comprise multiple customer accounts when
there are separate
         divisions, departments or subsidiaries that operate and make
purchasing decisions
         independently from the parent organization. We note that a group of
customers under
         common control or customers that are affiliates of each other shall be
regarded as a single
         customer for the purpose of disclosure regarding customer
concentration. Refer to Item
         101(c)(1)(vii) of Regulation S-K.
Management
Composition of Our Board of Directors, page 92

10.      Please identify the parties to the voting agreement as well as the
board members who were
         designated through the voting agreements with your Series A and B
preferred
         stockholders.
Executive Compensation
Employment Arrangements, page 98

11.      Your exhibit index indicates that you will file employment agreements
for Messrs.
         Pomel, Obstler, and Kopits that will be dated sometime in 2019. Please
advise us whether
         these agreements will be finalized and filed on a pre-effective basis.
If so, please provide
         a description of material terms of such compensation agreements when
available.
Certain Relationships and Related Party Transactions, page 108

12.      Please identify the "certain investors" that you entered into an
agreement to waive certain
         transfer restrictions in connection with the tender offer. In
particular, clarify
         whether parties to this agreement included the investors that
purchased shares in the
         tender offer. For the tender offer investors, also please clarify
whether they would be
         subject to the 180-day lock up agreement and receive any other rights
and privileges
         beyond those afforded to all Class B stockholders, such as
registration rights.
Principal Stockholders, page 110
FirstName LastNameOlivier Pomel
13.    Please disclose the natural person(s) holding investment and/or voting
power over the
Comapany NameDatadog, Inc. held by principal stockholders that are entities,
such as the funds
       shares of common stock
July 10, 2019 Page 3 Open Venture Partners, ICONIQ Strategic Partners, and RTP
Ventures.
       affiliated with
FirstName LastName
 Olivier Pomel
FirstName LastNameOlivier Pomel
Datadog, Inc.
Comapany NameDatadog, Inc.
July 10, 2019
July 10, 2019 Page 4
Page 4
FirstName LastName
Description of Capital Stock, page 113

14.      Please advise us whether your certificate of corporation will continue
to include the
         Excluded Opportunity provision, which would apply to your non-employee
directors. If
         so, provide a description of the Excluded Opportunity provision and
provide a risk factor
         given the inherent conflicts of interests with your Class B
stockholders and directors that
         are affiliated with venture capital firms.
15.      Please revise to provide a more detailed description of the material
voting rights of the
         Class A common stockholders. For example, disclose the circumstances
under which the
         Class A common stockholders are entitled to a separate class vote
under Delaware law.
Notes to Consolidated Financial Statements
Note 2. Basis of Presentation and Summary of Significant Accounting Policies
Deferred Contract Costs, page F-14

16.      Please tell us if additional sales commissions are paid upon contract
renewal and, if so,
         whether such amounts are commensurate with the initial commissions. To
the extent
         applicable, explain how commissions paid for renewals are considered
in your initial
         commission amortization period. Also tell us the period of time over
which you amortize
         commission costs related to contract renewals and revise your
disclosures, as necessary.
         Refer to ASC 340-40-35-1 and 340-40-50.
Note 10. Equity
Stock-Based Compensation, page F-27

17.      Please provide us with a breakdown of all stock options granted to
date in fiscal 2019 and
         include the fair value of the underlying common stock used to value
such awards as
         determined by your board of directors. To the extent there were any
significant
         fluctuations in the fair values from period-to-period, please describe
for us the factors that
         contributed to these fluctuations, including any intervening events
within the company or
         changes in your valuation assumptions or methodology. Also, tell us
how the
         $47.75 tender offer price impacted your valuations.
Note 12. Net (Loss) Income Per Share, page F-35

18.      Please revise to clarify whether the convertible preferred
stockholders have a contractual
         obligation to share in the company's losses. We refer you to ASC
260-10-45-68.
General

19.      Please supplementally provide us with copies of all written
communications, as defined in
         Rule 405 under the Securities Act, that you or anyone authorized to do
so on your behalf
         present in reliance on Section 5(d) of the Securities Act, whether or
not they retain the
         communications.
 Olivier Pomel
Datadog, Inc.
July 10, 2019
Page 5
20.   If you intend to use graphics in your prospectus, other than those
already provided, please
      submit such materials to the staff on a supplemental basis and provide
any support for any
      claims contained therein. Please refer to Question 101.02 of our
Compliance and
      Disclosure Interpretations relating to Securities Act Forms available on
our website.
        You may contact Eiko Yaoita Pyles, Staff Accountant, at (202) 551-3587
or Kathleen
Collins, Accounting Branch Chief, at (202) 551-3499 if you have questions
regarding comments
on the financial statements and related matters. Please contact Edwin Kim,
Staff Attorney,
at (202) 551-3297 or Jan Woo, Legal Branch Chief, at (202) 551-3453 with any
other questions.



                                                           Sincerely,

FirstName LastNameOlivier Pomel                            Division of
Corporation Finance
                                                           Office of
Information Technologies
Comapany NameDatadog, Inc.
                                                           and Services
July 10, 2019 Page 5
cc:       Nicole Brookshire, Esq.
FirstName LastName