← Glossary
RTB (Real-Time Bidding)
The auction mechanism that resolves each individual ad impression in real time as it's requested.
Real-time bidding is the underlying auction mechanism programmatic advertising runs on: when an ad impression becomes available, eligible bidders receive a bid request, respond within a strict time window (often under 100ms for CTV), and the highest qualifying bid wins and serves. OpenRTB is the IAB's standardized protocol for RTB bid requests and responses — RTB is the concept, OpenRTB is the specification most of the industry implements it with.