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The fast lane for the math you almost remember from school. Type the numbers, get the answer, move on with your day.
Try a scenario
Click to load — tweak from there.Inputs
Result
Arbitrage margin
3.33%
Stake on Side A
$235.09
Stake on Side B
$264.91
Guaranteed profit
$17.20
Guaranteed total return
$517.20
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter total amount to stake ($).
- 2Enter best odds, side a (american).
- 3Enter best odds, side b (american).
- 4Read your arbitrage margin on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
An arbitrage (arb) opportunity exists when two sportsbooks disagree enough about a two-outcome market that betting both sides at different books guarantees profit no matter which side wins. This happens when the combined implied probability of the best price on each side, from two different books, is under 100%. This calculator takes the best odds available on each side and your total bankroll for the arb, then splits the stake proportionally so both outcomes return the same profit. Real arbs are rare, usually small (0.5%-3% return), and short-lived because books adjust lines once volume shows up. They also carry practical friction: bet limits, account restrictions for consistent arbing, timing risk if one leg doesn't get matched before a line moves, and the hassle of managing money across multiple books. This tool does the math correctly; it doesn't account for withdrawal delays, promo terms, or a book limiting your account after repeated arb activity, all of which erode the theoretical edge in practice.
Worked example
Using the values the calculator loads with:
Inputs
- Total amount to stake: 500 $
- Best odds, Side A (American): 120
- Best odds, Side B (American): -105
Results
- Arbitrage margin: 3.33%
- Stake on Side A: $235.09
- Stake on Side B: $264.91
- Guaranteed profit: $17.20
- Guaranteed total return: $517.20
What each field means
Inputs
- Total amount to stake ($)
- The total amount to stake used in the calculation, measured in $. Starts at 500 $ so you have a working example on load.
- Best odds, Side A (American)
- The best odds, side a (american) used in the calculation. Starts at 120 so you have a working example on load.
- Best odds, Side B (American)
- The best odds, side b (american) used in the calculation. Starts at -105 so you have a working example on load.
Results
- Arbitrage margin
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Stake on Side A
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Stake on Side B
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Guaranteed profit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Guaranteed total return
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How do I know if a real arb exists?
Add the implied probabilities of the best available price on each side, from any two books. If the sum is under 100%, it's a positive arb, and the margin (100% minus that sum) is your guaranteed percentage return on the total staked, before factoring in fees or limits.
Why is a 2% arb considered good?
Because arbs are risk-free in theory, even a small guaranteed percentage beats savings account rates with none of the market risk. The catch is capital efficiency — your money is tied up per bet, opportunities are infrequent, and most books actively limit accounts that arb repeatedly, so this isn't a scalable strategy for most bettors.
What's the biggest practical risk with arbitrage betting?
Timing. If you place the first leg and the second book moves its line or limits your bet before you get the second leg down, you're left with a single unhedged bet instead of a locked arb. Fast execution and pre-checking bet limits at both books reduces this but doesn't eliminate it.
Will sportsbooks let me keep arbing?
Usually not for long. Books track betting patterns and often reduce limits or restrict accounts that consistently bet both sides of markets at the plus-EV price, since arb bettors contribute no long-run hold to the book. This is the main reason arbitrage betting isn't a sustainable full-time strategy for most people.
Accuracy and limitations
- Results are rounded for display; the underlying calculation keeps full precision.
- Very large or very small inputs may hit floating-point limits in the browser.
- Inputs outside the accepted range are clamped rather than rejected.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Arbitrage Stake Split Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/arbitrage-stake-split
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/arbitrage-stake-split" target="_blank" rel="noopener">Arbitrage Stake Split Calculator — RevenueLab</a> (2026).</p>
Source: [Arbitrage Stake Split Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/arbitrage-stake-split) (2026).