v3.26.1
Document and Entity Information
May 21, 2026
Document And Entity Information [Line Items]  
Document Type 8-K
Document Period End Date May 21, 2026
Entity Registrant Name Sensei Biotherapeutics, Inc.
Entity Incorporation State Country Code DE
Entity File Number 001-39980
Entity Tax Identification Number 83-1863385
Entity Address Address Line 1 1405 Research Blvd
Entity Address Address Line 2 Suite 125
Entity Address City Or Town Rockville
Entity Address State Or Province MD
Entity Address Postal Zip Code 20850
City Area Code 240
Local Phone Number 243-8000
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Security 12b Title Common Stock
Trading Symbol SNSE
Security Exchange Name NASDAQ
Entity Emerging Growth Company true
Entity Ex Transition Period false
Amendment Flag false
Entity Central Index Key 0001829802
Former Address [Member]  
Document And Entity Information [Line Items]  
Entity Address Address Line 1 451 D Street
Entity Address Address Line 2 Suite 710
Entity Address City Or Town Boston
Entity Address State Or Province MA
Entity Address Postal Zip Code 02210