A situation where the sum of implied probabilities across all outcomes of an event in different systems is less than 1. Allows betting on all outcomes simultaneously with guaranteed profit regardless of the result.
Polymarket, Kalshi, and Predict.fun are decentralized markets where users set prices. They often lag bookmakers or overvalue favorites, creating exploitable price gaps.
Prediction market prices update every 3 seconds via CLOB API. Fonbet and Winline bookmakers update every 2 seconds. Arbs appear almost instantly.
We recommend $500–1000: some with a bookmaker, some on Polymarket/Kalshi (USDC). PolyFork automatically calculates optimal stake amounts for your bankroll.
Arbitrage is a completely legal strategy. Prediction markets function as financial instruments. PolyFork is an information tool and does not place bets on your behalf.
On prediction markets you can only buy a limited number of shares at the current price. Liquidity depth shows the maximum USD amount you can realistically enter right now.