When you place a bid, you enter the maximum amount you're willing to pay for the item. The seller and other bidders won't know your maximum bid amount.

This site places bids on your behalf starting with the next bid increment for the auction. The system will bid as much as necessary to make sure that you remain the high bidder. We'll keep bidding for you until bidding reaches your maximum amount (proxy bid).

If another bidder has placed the same bid before you or a higher maximum bid, the system will let you know that you've been outbid so that you can place another bid if you want. However, if no other bidder has a higher maximum bid at the end of the auction, you will win the item even if your bid doesn't go as high as your maximum bid. You may pay significantly less than your maximum price. This means you don't have to keep coming back to re-bid every time another bid is placed.