Implied probability

The probability a market price states directly: a contract at 30¢ implies roughly a 30% chance, before fees.

The fixed dollar payout is what makes this direct. There is no odds conversion to perform, because the venue quotes probability in cents. Prediction markets have prices, not odds, and this is the reason people find them easier to reason about than any other forecasting instrument.

Two corrections turn a quoted price into a number you can compare with your own view. First, use the executable ask rather than the last print, since the last print is a price somebody got and not one you can have. Second, add the fee, because your breakeven is the all-in cost and not the sticker. A Kalshi contract asking 40¢ carries about 1.7¢ of fee, so it implies a breakeven near 41.7 percent — you need to be right about 41.7 percent of the time, not 40, before the trade is worth doing at all.

One more read that costs nothing: in a two-sided book, the YES ask and one minus the NO ask bracket the market's implied range. A tight bracket means the book is confident. A wide one means it is telling you it does not know, and you should be sceptical of any model that claims precision the market itself is not claiming.

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Related terms

Definitions describe how Polymarket and Kalshi behave and how WhaleTracks models them; venue rules and fee schedules can change, so confirm anything you size a position on with the venue itself. WhaleTracks is informational analytics, not financial advice. Past performance does not guarantee future results.