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Parlay calculator

Combined odds, payout and implied chance for up to 12 legs. Add a fair win % per leg and see the parlay's true chance and EV.

FreeNo account neededSame math as our tools

Inputs

$

Result

updates as you type

Run this math on every line, automatically

Use the +EV finder to price each leg against the market before you combine them.

Price legs on Sportsbook PropsLearn how it works

How it works

A parlay pays only if every leg wins. Its decimal price is the product of the legs' decimal prices, and if the legs are independent its true chance is the product of their true chances:

D = d1 × d2 × … × dn · payout = stake × D

true chance P = p1 × … × pn · EV = P × D − 1

The implied chance 1/D carries every leg's vig, multiplied together, which is why parlays usually have a bigger house edge than single bets. Enter a fair win % on each leg (from the no-vig calculator or our tools) to see whether the combination is actually +EV.

Worked example

Three legs: −110, −110 and +150, $10 staked.

D = 1.9091 × 1.9091 × 2.5000 = 9.1116 (+811)

Payout = $10 × 9.1116 = $91.12; implied chance 1/9.1116 = 10.98%

If the fair chances are 50%, 50% and 42%: true chance = 10.50%, EV = 0.1050 × 9.1116 − 1 = −4.33%

Each −110 leg at a 50% fair chance is −EV on its own, and multiplying them keeps the parlay −EV even though the payout looks large.

Things to watch

  • Vig compounds. Three −110 legs carry roughly three times the margin of one.
  • Correlation. Legs from the same game are not independent; this calculator multiplies chances and does not model correlation.
  • Book rules. A push or void usually drops that leg and reprices the parlay; rules differ by book.

Frequently asked questions

How are parlay odds calculated?
Multiply the decimal odds of every leg. For example −110, −110 and +150 are 1.9091 × 1.9091 × 2.5 = 9.11 in decimal, about +811.
Are parlays ever +EV?
Only if each leg is +EV or the legs are positively correlated in a way the book has not priced. Multiplying −EV legs makes the parlay more −EV.
Does this handle same-game parlays?
No. It assumes independent legs. Same-game legs are correlated, and books price same-game parlays with their own models.
What happens if a leg pushes?
Most books remove the pushed leg and pay the parlay at the remaining legs' odds. Check your book's rules.

Related calculators

Expected value (EV) calculatorEV, edge and Kelly from a fair %, fair odds or a two-sided market with the vig removed.No-vig fair odds calculatorFair odds with five devig methods side by side, 2- to 6-way markets.Implied probability calculatorBreak-even win % for any price; add the other side for the no-vig fair.Pick'em break-even calculatorPer-leg break-even for PrizePicks, Underdog, Dabble and more; entry EV.

Learn more

Intro to +EV bettingPositive expected value means a price pays more than its fair odds. Here's how to find the fair odds and what the edge really means.Pick'em optimizer: pricing PrizePicks, Underdog and DabbleEach app's payout table sets the win rate every leg needs. Fair probabilities from the betting market tell you which legs clear it.