v3.25.4

Cover	Mar. 04, 2026
Document Information [Line Items]
Document Type	8-K
Document Period End Date	Mar. 04, 2026
Entity Registrant Name	Keros Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-39264
Entity Tax Identification Number	81-1173868
Entity Address, Address Line One	1050 Waltham Street
Entity Address, Address Line Two	Suite 302
Entity Address, City or Town	Lexington
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02421
City Area Code	617
Local Phone Number	314-6297
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001664710
Amendment Flag	false
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	KROS
Security Exchange Name	NASDAQ
Preferred Stock
Document Information [Line Items]
Title of 12(b) Security	Preferred Share Purchase Rights
Security Exchange Name	NASDAQ
No Trading Symbol Flag	true

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Keros Therapeutics, Inc. 8-K