Two statisticians from the University of Maryland have calculated that eBay buyers saved $7 billion than what they might have been willing to pay in 2003, $8.4 billion in 2004 and a projected $19 billlion during 2007. The savings is determined by calculating "consumer surplus" or the difference between what top price buyers were willing to pay and what they actually ended up paying. On eBay, winning bidders pay the next highest increment after the second highest bidder was willing to pay. The difference between each winning bid and what the buyer ends up paying is the consumer surplus.

Most of the data was taken from Cniper.com, operated by Bapna. Cniper allows consumers to automatically bid in the closing minutes of auctions to help get the item at the lowest possible price.