Real-Time Bidding (RTB)
An auction-based mechanism for buying and selling digital advertising impressions instantaneously as they become available.
Real-Time Bidding (RTB) is the technology and process by which digital advertising impressions are bought and sold through instantaneous auctions that occur in the milliseconds between a user arriving at a page or a screen becoming available and the advertisement being displayed.
When an advertising impression becomes available — whether on a website, app, or digital screen — the publisher's SSP sends a bid request to connected DSPs containing information about the impression: location, screen size, audience data, time of day, and other contextual signals. Each DSP evaluates the opportunity against its active campaigns and submits a bid. The highest bidder wins the impression, and their creative is served to the screen — all within approximately 100 milliseconds.
RTB is the foundational mechanism of programmatic advertising. For retail media networks, RTB enables in-store digital screens to be monetised through the same automated, data-driven buying process used for online display advertising, making in-store inventory accessible to the global programmatic advertising ecosystem.