Sure Bet (Arbitrage) Calculator

Free sure bet and arbitrage calculator: enter odds from multiple bookmakers, instantly see if an arb exists, and get exact stakes to guarantee profit on any.

How sure bets (arbitrage) work

Arbitrage in sports betting exploits price discrepancies between bookmakers. Because different bookmakers have different opinions (and different liabilities) on the same outcome, they occasionally offer odds that, when combined across the market, imply a total probability below 100%.

For example: in a football match, Bookmaker A offers Home Win at 3.20, Bookmaker B offers the Draw at 3.40, and Bookmaker C offers Away Win at 2.30. The implied probabilities are: 31.25% + 29.41% + 43.48% = 104.14% — no arb. But if Bookmaker B moved Draw to 3.60, the sum becomes 31.25% + 27.78% + 43.48% = 102.5% — still no arb. It isn't until the sum drops below 100% that a guaranteed profit exists.

Calculating optimal stakes for an arb

The formula for the optimal stake on each outcome is: Individual Stake = (Total Bankroll / Sum of Implied Probs) × (1 / Outcome Odds) . This distributes your total bankroll across all outcomes so that every possible result returns the same guaranteed profit — regardless of which team wins or draws.

Risks and practical considerations

Pure arbitrage is theoretically risk-free mathematically, but practical risks exist: odds can change or be voided before all legs are placed; bookmakers may refuse large stakes or void bets at non-standard prices; minimum/maximum stake limits vary. Always confirm odds are still available on all platforms before placing all legs simultaneously.

Legal and responsible use

Arbitrage betting is legal in most jurisdictions. It's a sophisticated strategy used by professional bettors and quantitative trading operations. SmartMatchPick does not promote reckless gambling — always bet within your means and understand the practical risks outlined above.