Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 07, 2022
Document and Entity Information
Entity Registrant Name	908 DEVICES INC.
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2022
Entity File Number	001-39815
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-4524096
Entity Address, Address Line One	645 Summer Street
Entity Address, City or Town	Boston
Entity Address State Or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	857
Local Phone Number	254-1500
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	MASS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		31,407,398
Entity Central Index Key	0001555279
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false