Add up to 12 legs in American odds. We multiply the decimal odds for every leg, apply your stake, and show the true payout, profit, and implied win probability. Last updated: May 2026.
| # | American Odds | Decimal |
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A parlay combines multiple bets into one wager. The decimal odds of every leg are multiplied together, then multiplied by your stake. Every leg must win or the whole parlay loses.
Convert each leg to decimal odds first. Positive American odds: (odds ÷ 100) + 1. Negative American odds: (100 ÷ |odds|) + 1. Multiply all decimals together to get the parlay's combined decimal odds.
Mathematically, parlays carry a higher hold (built-in house edge) than single bets because the vig compounds with each leg. They can still be +EV if every individual leg is itself +EV, but most casual parlays are -EV.
This calculator supports up to 12 legs. Most sportsbooks cap parlays somewhere between 10 and 25 legs, so 12 covers nearly every real-world bet slip.
Each leg has its own implied probability under 100%. Multiplying probabilities (which is what a parlay is in math terms) compounds them downward fast — a 5-leg parlay with each leg at -110 has only about a 3% true win probability.