Glossary/Adtech & Programmatic/Ad Exchange
Adtech & Programmatic
Ad Exchange
A digital marketplace where buyers and sellers trade ad impressions, usually via real-time auctions.
By Brandon Mina·CEO, BrandPilot AI·Updated November 2026
Appears in Lesson 1 of Programmatic 101
Short answer
An ad exchange is a digital marketplace where advertisers and publishers buy and sell ad impressions, usually through automated real-time auctions. Demand-side platforms submit bids on behalf of buyers, while supply-side platforms offer publisher inventory. Exchanges set auction rules and clear transactions in milliseconds, making them the central trading venue of programmatic advertising.