Bankroll Guardian

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Arbitrage calculator

Find guaranteed-profit two-way bets.

Stake A

48.84

Stake B

51.16

Payout

107.44

Profit

+7.44

Arbitrage — the two prices imply 93.07% (under 100%). Stake 48.84 on A and 51.16 on B for a guaranteed 7.44 (7.44% ROI) either way.

Enter the best price for each side from different sportsbooks. An arb exists only when the combined implied probability is under 100%.

How arbitrage works

An arbitrage (or “arb”) happens when two sportsbooks price the same market far enough apart that you can back both sides and profit no matter the result. It exists when the combined implied probability of the two best prices is under 100% — the calculator then splits your stake so the return is identical either way.

Arbs are usually small and short-lived, and stake limits or a line move can erase them before you’re set. Treat this as a line-shopping tool: the same best-price discipline that surfaces arbs is what wins long-term value. Log both legs in Bankroll Guardian so your CLV and ROI stay accurate.

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Track every bet automatically

Stop doing the math by hand. Bankroll Guardian logs your bets and shows P&L, ROI, CLV and more — free to start, no card required.

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