What does reciprocal odds index mean?

It is the sum of 1 divided by each decimal odd. Below 1 means the prices are mathematically favorable across all outcomes.

Why can rounded stakes change the result?

Rounding whole-dollar stakes makes payouts slightly uneven, so the worst and best result can differ.

Is arbitrage betting risk-free?

No. The formula can be positive, but execution, limits, grading rules and odds changes can still create losses.

Arbitrage Betting Calculator

Check whether odds across sportsbooks create a surebet, then calculate stake allocation, payout, worst-case result and ROI.

Market type

Odds from different sportsbooks

Outcome

Sportsbook

Odds

2 of 6

Stake calculation mode

Total bankroll, $

Round stakes to whole dollars

Enter odds for every outcome (values greater than 1) to calculate arbitrage and stake allocation.

Check whether odds create a surebet

Arbitrage betting intent expects a quick reciprocal-odds check and a stake split. If the sum of 1 divided by each decimal odd is below 1, the entered odds produce a positive calculated result before execution risk.

I n d e x = i = 1 \sum n \frac{1}{O dd s _{i}}

Index below 1 indicates an arbitrage opportunity on the entered prices.

Execution risk still matters

Real-world arbitrage can fail if odds move, limits are lower than expected, a market is graded differently, or one bet is rejected. Treat the output as math for entered odds, not a guarantee.

Betting involves risk and legal restrictions. Use this as a calculation aid only.

Frequently Asked Questions

Sources and References

Calculations are based on the listed reference sources. Links open in a new tab.

Updated: June 2, 2026

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