Trading Tools
Calculators
Professional market-mechanics and risk calculators. Every tool is educational — explore the math behind odds, value, and position sizing.
Odds & Probability
Market Mechanics
Risk & Value
Arbitrage
Market Mechanics · Cross-book guaranteed profit
Combined Overround
103.6%
No arbitrage — margin exceeds 100%
Arbitrage exists when the best odds for every outcome (across different bookmakers) sum to less than 100% implied probability. The calculator splits your stake so the return is identical regardless of the result. Arbs are rare, short-lived, and shrunk by bookmaker margins — they illustrate market efficiency, not a reliable income stream.