| # | Odds (decimal) | Stake | Return if wins |
|---|
An arbitrage calculator (also called an arb calculator or arbing calculator) checks whether the odds offered by different bookmakers on the same event create a guaranteed-profit opportunity. When the combined implied probability of all outcomes is below 100%, you can distribute your stake so that you profit no matter who wins.
Two bookmakers disagree on a tennis match. Bookmaker A offers Player X at decimal odds 2.10. Bookmaker B offers Player Y at decimal odds 2.20. Your total stake is $1,000.
Both outcomes return approximately the same amount. The $0.01 difference is because stakes are rounded to the cent — the calculator takes the minimum return as the guaranteed return, so the profit figure you see is the worst-case scenario.
This tool accepts three odds formats. Use the dropdown on each outcome to switch:
2.10. The most straightforward format. Implied probability = 1 / decimal odds.+150 or -200. Positive odds: decimal = (American / 100) + 1. Negative odds: decimal = (100 / |American|) + 1.3/2. Decimal = (numerator / denominator) + 1. Enter as 3/2, 5/1, 10/11, etc.An arbitrage bet (or "arb") is when you place bets on all possible outcomes of an event across different bookmakers, exploiting odds discrepancies so that you lock in a guaranteed profit regardless of the result. An arbitrage betting calculator does the math for you — it converts the odds, checks if a profit is possible, and tells you exactly how much to stake on each outcome.
The calculator supports any number of outcomes from 2 upward. Two-way markets (e.g. tennis, basketball moneyline) and three-way markets (e.g. soccer win/draw/loss) are both handled. Click "Add outcome" to add more legs.
No. You enter the odds you found manually. This tool does the math — it does not pull live odds from any bookmaker. Real-time odds scanning requires a paid subscription service; this calculator is free and runs entirely in your browser.
No. There is no registration, no login, and no popup. Open the page and use it.
Stakes are calculated to the cent (two decimal places). Due to rounding, there may be a $0.01 difference between what each leg returns — this is normal and unavoidable when working with cents. The guaranteed profit figure accounts for this.
The math is risk-free — if both bets are placed and accepted at the odds you entered, the profit is locked in. In practice, risks include odds changing before you place the second bet, a bookmaker rejecting or voiding a wager, and account limitations on bettors who arbitrage frequently. This calculator does not eliminate execution risk; it only handles the calculation.