Parlay Calculator

How parlay odds work

A parlay combines two or more individual bets into a single wager. Every leg must win for the parlay to cash — one loss and the whole ticket is dead. The payoff is calculated by converting each leg to decimal odds and multiplying them together. Three legs at –110 each convert to 1.909 in decimal, and 1.909 × 1.909 × 1.909 ≈ 6.96 — roughly +596 in American odds.

Here's the part most bettors miss: if each of those legs is a true coin flip, the fair probability of hitting all three is 50% × 50% × 50% = 12.5%, which should pay +700. The gap between +700 and +596 is the sportsbook's vig — compounded across every leg. The more legs you stack, the wider that gap grows.

How to use this calculator

1. Choose your odds format. Toggle between American (e.g. –110) and Decimal (e.g. 1.909). Switching format converts all existing leg values automatically.
2. Enter your stake. The dollar amount you're putting on the ticket. Payout and profit update as you type.
3. Add your legs. Enter the odds for each bet in the parlay as listed at your sportsbook. Use + Add leg to build tickets up to 12 legs. The Implied Prob column shows what each leg's price says about its win probability.
4. Read the results. Combined Odds is the price of the full ticket. Total Payout is what the book returns if everything hits, and Profit is that amount minus your stake. Implied Probability is how often the whole ticket must win for the bet to break even.

The math working against you

Parlays are the most profitable bet type sportsbooks offer — for the sportsbook. On a single –110 bet, the built-in house edge is about 4.5%. Parlay two –110 legs and the edge compounds to roughly 9%. At three legs it's near 13%, and a five-leg ticket hands the book close to 20% before kickoff. You're not just paying juice once; you're paying it on every leg, multiplied together.

That doesn't mean parlays are never worth analyzing. If you genuinely hold an edge on each individual leg, that edge compounds the same way the vig does — but your per-leg edge has to be large enough to overcome the stacked juice, which is a high bar. For most bettors, the disciplined play is straight bets at the best available price. Use this calculator to see exactly what a ticket pays and what it implies — and compare the implied probability against your honest assessment of how often that ticket actually cashes.