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Fee and break-even calculator

Exact fee, cost, payout and break-even probability for Kalshi and Polymarket trades.

Cross-exchange gap calculator

Does a Kalshi vs Polymarket price gap survive fees?

Prediction market cheat sheet (PDF)

Fee formulas, odds conversion and a pre-trade checklist on one page.

Live price comparison

Every event listed on both Kalshi and Polymarket, updated every 10 minutes.

Price-gap statistics

How often the two exchanges disagree, from our own hourly data.