Free tool
Parlay calculator
Enter the American odds for each leg and your stake to instantly see your combined parlay odds, total payout, and implied win probability. Add up to 12 legs.
American odds only · up to 12 legs · implied probabilities include vig
How parlays multiply
Each leg's decimal odds multiply together, then by your stake. Two -110 legs (1.909 each) make 3.64x, so a $100 parlay returns $364.55. The payout grows fast, but so does the chance of one leg busting the whole ticket.
The hidden cost of parlays
Because the vig compounds on every leg, parlays carry a far higher house edge than single bets. The calculator shows the true combined win probability next to the payout, so you can see exactly what you're being paid to take on.
Frequently asked
What is a parlay bet?
A parlay combines two or more individual bets into a single wager. Every leg must win for the parlay to pay out. The odds from each leg multiply together, creating a much larger potential payout than betting each game separately, but at a significantly lower probability of winning.
How is a parlay payout calculated?
Convert each leg's American odds to decimal, multiply all the decimals together for the combined multiplier, then multiply by your stake. Two legs at -110 each become 1.909 × 1.909 × $100 = $364.55 payout ($264.55 profit).
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