Parlay calculator odds: what a multi-leg price really pays
- Profit if every leg wins
- $701.82
- First leg as decimal odds
- 1.91
- Second leg as decimal odds
- 1.91
- Third leg as decimal odds (1.00 when it is not in the parlay)
- 2.20
Every figure on this site comes out of the prices you type and the arithmetic printed beside them. There is no feed, no price of our own and no third-party data: the site holds no odds at all, only the method for reading the ones you already have. Conversions are exact, not approximations, and the American-to-probability step is written out on each page so you can check it by hand.
The prices above are a worked example ($701.82). Type the two you are actually looking at and every line re-computes.
Download the Parlay Calculator Odds and Payout worked example (CSV)
Give it between two and four American prices and a stake and it converts each leg to decimal odds, multiplies them into one price for the whole parlay, converts that back to American odds, and shows what comes back if every leg wins along with the probability the combined price implies. Three legs at minus 110, minus 110 and plus 120 multiply to 4.00, which is plus 300 and a 25% implied probability. The margin on each leg compounds, which is what the implied probability at the bottom is there to show.
Parlay Calculator Odds and Payout: what people ask about the arithmetic
How is a parlay price worked out?
Each leg is converted to decimal odds and the decimals are multiplied together. Nothing else happens: a parlay price is the product of its legs, and the American figure the calculator shows is that product converted back.
Why is the implied probability so low?
Because probabilities multiply as well. Two legs at 52.38% give 27.44%, and each leg also carries its own margin, so the charge compounds across the parlay as surely as the price does. The implied probability is the honest way to see it.
Can I put in fewer than four legs?
Yes. Choose two, three or four at the top and the unused legs are set to decimal 1.00, which multiplies to nothing and leaves them out of the price entirely.
Does this account for legs that are related?
No, and no multiplication can. Multiplying assumes the legs are independent. Where two legs are on the same game or the same team, the true probability is not the product and the calculator's figure is a reference point rather than an answer.
Where the method behind this calculator comes from
Wolfers and Zitzewitz, Prediction Markets (Journal of Economic Perspectives, NBER working paper 10504). Sets out the standard reading of a market price as a probability, and the conditions under which that reading holds.
CFTC, Designated Contract Markets (DCMs). The regulator's own list of the venues on which event contracts trade in the United States. Named here because readers arrive from those markets; this site links to none of them.