Cover - USD ($) $ in Thousands	12 Months Ended
Cover - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 31, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K/A
Amendment Flag	true
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Document Transition Report	false
Entity File Number	001-39637
Entity Registrant Name	DATTO HOLDING CORP.
Entity Central Index Key	0001724570
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-3345706
Entity Address, Address Line One	101 Merritt 7
Entity Address, City or Town	Norwalk
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06851
City Area Code	888
Local Phone Number	995-1431
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	MSP
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		163,998,932
Documents Incorporated by Reference	None
Entity Public Float			$ 1,200,000
Entity Filer Category	Large Accelerated Filer
Amendment Description	Datto Holding Corp. (the “Company”) is filing this Amendment No. 1 (the “Amendment”) on Form 10-K/A to amend its Annual Report on Form 10-K for the fiscal year ended December 31, 2021, filed with the Securities and Exchange Commission on February 23, 2022 (the “Original 10-K”), for the purpose of filing revised versions of Exhibits 31.1 and 31.2 filed with the Original 10-K.The Company is filing revised exhibits solely in order to include in the certifications set forth in the Exhibits the language regarding internal control over financial reporting in revised paragraph 4 and 4(b), which language was inadvertently omitted from the certifications when filed with the Original 10-K. The Amendment does not modify, amend or update the financial or other information contained in the Original Filing, or in any way reflect events occurring after the date of the filing of the Original 10-K. Accordingly, the Amendment should be read in conjunction with the Original 10-K. The Amendment consists solely of the cover page, this explanatory note, the exhibits listing, the signature page and paragraphs 1, 2, 4 and 5 of each of the revised certifications filed as exhibits to the Amendment. Because no financial statements have been included in this Amendment, paragraph 3 of each of the certifications set forth in the Exhibits has been omitted Pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended. This Form 10-K/A contains new certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, which are attached hereto.The Amendment does not include a new audit opinion of Ernst & Young LLP (PCAOB ID 42) Stamford, Connecticut.

DATTO HOLDING CORP. 10-K/A