What is programmatic advertising?
Programmatic advertising is the automated buying and selling of digital ads through software, instead of manual negotiations and insertion orders. Buyers use platforms that decide, impression by impression, which ads to buy and what to pay, often through real-time auctions that finish in a fraction of a second. It covers display, video, CTV, audio, mobile apps and digital billboards.
In programmatic advertising, an advertiser's DSP connects to publishers' SSPs and ad exchanges. When a page or app has an ad slot to fill, the seller sends a bid request describing the opportunity; buyers respond with bids, and the winner's ad is served. Most of this runs on the OpenRTB protocol.
Programmatic is not only open auctions. Buyers can also transact through private marketplace deals and programmatic guaranteed buys, which automate direct relationships. The IAB/PwC reports put US internet advertising revenue at $294.6 billion for 2025; programmatic pipes carry a large share of the non-search, non-social part of that spend.