Systems and methods for optimizing floor prices in real-time bidding auctions are described. Upon receiving a request for an advertisement to be served to an impression consumer, the value of the consumer can be determined based, for example, on historical bid prices in prior auctions. A maximum floor price for the current auction to serve the impression us calculated based at least in part on the value of the impression consumer and one or more attributes associated with the auction. The auction is held using the calculated floor price, which can be adjusted based on an aggressiveness factor, and the winner of the auction can be determined based on the floor price.