Tophatter is an auction site with short period auctions that only last a few minutes. Since there isn't much time, you rarely can make a good informed decision on what a fair bid price is for an auction. To compensate, I made this site which keeps track of past winning bids for Tophatter.com auctions.
Find an auction on Tophatter
First, you'll need to go to tophatter.com and find something interesting.
I could use this Damaged Screw Extractor bit set. Click it to bring up the details.
See the the name of the product at the top: "4 Pcs Broken Bolt and Damaged Screw Extractor with Case Remove All Kinds of Screws and Bolts". You can see what this auction has ended at previously here on biddingstats.com.
Look Up the Product Name on BiddingStats.com
You can either find the auction's listing by browsing through the list of currently active tophatter auctions, or you can do a search by clicking on "Search" at the top of the page.
Then type in a few key words from the product's title into the search box.
Next you should see your results. If there are more results than you were expecting, you can filter to just the category of what you're interested in by clicking one of the categories at the top. (Electronics, jewelry, etc...)
Click on the name of the same product that you were just looking at on Tophatter. It should open up a chart which will tell you past wins this product has sold at.
Each bar in the chart represents how many times the auction has ended at that price. In this example, the Damaged Screw Extractor sold for $2 six times, which is the lowest price it can sell for. Most often it sold for $6, which happened sixteen times.
Improve your Bidding On Tophatter
Use the bid statistics to decide if this is a good auction to keep bidding on, or if you should wait until the next time it is listed to try to grab it for less.
If you are interested in selling on Tophatter, you can use this historical bid data to determine which types of products you can get the most money for. You could also compare different listings of the same product to see which garners more attention.
Good Luck, and happy bidding!