Frequently asked questions
Does this cover Polymarket US?
No. We cover Polymarket's international, on-chain platform, where every trade is tied to a public wallet; that's what makes wallet track records possible. Polymarket US is a separate CFTC-regulated exchange with its own data, and as of October 2026 it's the bigger of the two by volume, mostly sports. If it publishes trade data we can grade, we'll add it as its own clearly labeled venue, like Kalshi.
Is WhaleGrader financial advice?
No. WhaleGrader reports what large Polymarket traders did and how those positions resolved. Nothing on the site is a recommendation to trade.
Where does the data come from?
Polymarket's public APIs: the Data API for trades, the Gamma API for market metadata and resolutions, and the CLOB API for price history. The live tape reads new trades every 10 seconds; stored, graded flags refresh every 15 minutes.
What counts as a whale flag?
A taker trade of $10,000 or more. Fills by the same wallet on the same market and side within an hour are merged into one flag. We also flag markets whose price moved 10+ points in 24 hours on at least $25,000 of volume.
How is a flag graded?
When the market resolves, the flag is called if its side won and missed if it lost. Each flag also carries an expected win rate equal to its entry price. Edge is called minus expected, divided by the number of flags.
Why adjust for price?
A whale taking a 90¢ favorite will be right about 90% of the time by default. Raw hit rates reward buying favorites. Comparing to the price paid shows whether the flag beat the market's own odds.
Why are some flags excluded from the scoreboard?
Trades placed less than an hour before a market starts or closes are shown but not scored. Late trades often reflect information the market already has, such as a game in progress.
Which markets do you cover?
Polymarket only, across sports, politics, crypto, economics and everything else listed there.
Do you know who owns a wallet?
No. Wallets are public, pseudonymous on-chain addresses. We show them abbreviated and link to their public Polymarket profile.
How do I get alerts?
Save rules on the alerts page (a wallet, a market, any proven or losing wallet, HIGH severity). Matches show live on that page, and you can send them to a Discord or Slack webhook or a private RSS feed today. Telegram and email are being switched on.
Still curious? Read the methodology.