How we scan
Every few hours BundleScan reads the bundle listings on Humble Bundle and Fanatical and records each bundle's tiers, prices, items, end date and charity.
Steam prices
For each game we find its Steam store page and check today's Steam price, in the same currency as the bundle. Every deal page says when the prices were checked. A game is only counted when we are confident it is the same game, so some games show no Steam price.
Savings
"You save" compares what a tier costs with what the same games cost on Steam on the day we checked. For pick-and-mix bundles we compare against the priciest games you could choose. MSRP is the store's own list value.
End dates
Countdowns use the store's own end time. When a deal ends, its page stays up, is marked as expired, and points you to similar bundles that are still live.