← Back to glossary
Advertising Platforms & Infrastructure
3 min read
An ad exchange is a digital marketplace where advertisers and publishers buy and sell ad impressions in real time, usually through automated auctions. It is the trading floor of programmatic advertising — the place where a single impression is priced and sold in the milliseconds before a page loads.
A page loads. An available impression is put up for sale.
The auction opens. Buyers bid for that impression in real time.
The winner is chosen. The highest eligible bid takes the slot.
The ad serves. All of it happens before the page finishes rendering.
Advertisers via DSPs. Buyers bid through demand-side platforms.
Publishers via SSPs. Sellers offer inventory through supply-side platforms.
The exchange. The neutral marketplace that runs the auction.
Data providers. Signals that help buyers value each impression.
Efficiency. It matches supply and demand automatically at scale.
Reach. Buyers access inventory across many publishers at once.
Real-time pricing. Every impression is valued on its own merits.
Transparency. It can be hard to see where money and impressions go.
Quality. Not all exchange inventory is premium or safe.
Fraud. Automated marketplaces attract invalid traffic.
Fees. Each intermediary takes a cut of the spend.
Keep exploring
Browse all 61 advertising terms
→
OpenAds connects your assistant to every major ad platform, so you can plan, launch and optimise campaigns in plain language — approving the moves that matter.
Explore OpenAds