Header Bidding

A technique that lets publishers offer inventory to multiple demand sources at once before calling their ad server.

By Brandon MinaCEO, BrandPilot AIUpdated November 2026

Short answer

Header bidding is a technique that lets publishers offer ad inventory to multiple demand sources simultaneously before calling their ad server. Competing bids are passed to the ad server, which compares them against other demand. Compared with the older waterfall method, header bidding increases competition, improves transparency, and typically raises publisher revenue.

A packed auction hall where everyone raises bidding paddles at once toward a stage shaped like a web browser window with an open ad slot. 1960s ink-and-gouache magazine-ad illustration. — Header bidding: every buyer bids on the slot at the same time.