Demand-Side Platform (DSP)

Also known as: DSP

An AdTech platform that enables agencies and advertisers to purchase ad inventory from Supply-side platforms (SSPs) and ad exchanges. DSPs are typically used to buy inventory on an impression-by-impression basis, with each purchase decided through a Real-time bidding (RTB) auction.

In practice, a DSP sits on the buyer's side of a programmatic transaction: it aggregates available inventory signals, evaluates each impression against campaign targeting criteria and bid prices, and submits bids automatically at auction speed. This makes DSPs the primary tool through which advertiser demand flows into the open programmatic ecosystem.