v3.26.1
Document and Entity Information
Mar. 19, 2026
Cover [Abstract]  
Entity Registrant Name ON24 INC.
Amendment Flag false
Entity Central Index Key 0001110611
Document Type 8-K
Document Period End Date Mar. 19, 2026
Entity Incorporation State Country Code DE
Entity File Number 001-39965
Entity Tax Identification Number 94-3292599
Entity Address, Address Line One 301 Howard Street
Entity Address, Address Line Two Suite 1100
Entity Address, City or Town San Francisco
Entity Address, State or Province CA
Entity Address, Postal Zip Code 94105
City Area Code (415)
Local Phone Number 369-8000
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Security 12b Title Common stock, par value $0.0001 per share
Trading Symbol ONTF
Security Exchange Name NYSE
Entity Emerging Growth Company true
Entity Ex Transition Period false