INQSI GUIDE
What Is Sports Arbitrage?
A plain-English explanation of sports arbitrage, implied probability and execution risk.
Sports arbitrage exists when prices available across outcomes imply a combined probability below 100%. In the mathematical ideal, stakes can then be allocated so the gross payout exceeds the total amount staked regardless of which covered outcome wins.
Real markets add execution risk. Prices can move, limits can differ, markets can be suspended, and books can use different settlement rules. A calculation therefore needs current, matching, confirmed quotes.
What to check
- Convert every price to decimal or implied probability
- Add the implied probabilities for all mutually exclusive outcomes
- A total below 100% is the mathematical arbitrage condition
- Verify freshness, limits and settlement before relying on the calculation