Add as many legs as you want. Mix American, decimal, and implied probability freely, we convert them all to decimal under the hood and compute combined odds, win probability, and payout.
Legs (3)
1
2
3
Parlay Result
Combined odds+702 · 8.018
True implied probability12.47%
Stake$10.00
Profit$70.18
Total payout$80.18
Combined odds assume each leg is independent. Same-game parlays are not independent, the real fair price is usually worse than this.
How parlay math works
A parlay multiplies the decimal odds of each leg: combined = d₁ × d₂ × … × dₙ. Total payout = stake × combined. Profit = payout − stake.
Each leg must hit or the parlay loses. This stacks the sportsbook's vig on every leg, which is why straight multi-leg parlays at standard pricing have meaningful negative EV. The route in is to build parlays entirely from +EV legs, or from +EV correlated legs in an SGP.
Frequently asked questions
How do you calculate parlay odds?+
Multiply the decimal odds of each leg. A 3-leg parlay at 1.91 × 1.91 × 1.91 = 6.97 decimal, or about +597 American. The implied probability is 1 / 6.97 = 14.35%.
Are parlays a good bet?+
Standard parlays carry compounded vig: each leg has the book’s margin baked in, and parlays multiply that margin. They have positive EV only if every individual leg is +EV. DFS-style parlays (PrizePicks, Underdog) use fixed payouts (1.84x – 6.5x for 2–3 legs) and can be +EV if your model edge is high enough.
What is a same-game parlay (SGP)?+
A parlay where multiple legs are from the same game. Books price SGPs with a correlation adjustment because the legs are not independent, for example, a QB throwing for 300 yards correlates with a WR going over receiving yards. Sharp SGP betting requires modeling correlation explicitly.
Does this calculator handle DFS parlays like PrizePicks?+
Yes, paste the fixed payout (1.84 decimal for 2-leg PrizePicks, 3.5 decimal for 2-leg Underdog Power, 6.5 for 3-leg, etc.) as one leg. For a true DFS lineup with multiple props at fixed payouts, enter each prop as a separate leg.
What is the true probability of my parlay?+
It is the product of each leg’s true probability, the probability you get from a probability model, not implied probability. The Turtle +EV picks platform shows true probability for every prop our model evaluates.
Calculators are free. The Turtle +EV picks platform runs every prop through a sport-specific model and ranks the ones where the line is mispriced. MLB · Soccer · Tennis · WNBA. 30+ books.