How parlay odds are calculated
A parlay is one ticket built from two or more individual bets — ‘legs.’ Every leg has to win. In exchange, the sportsbook multiplies your odds together instead of adding them: each leg’s odds are converted to decimal form, multiplied into one combined number, and that number times your stake is the payout.
Take a $100 three-leg parlay: one leg at −110 (decimal 1.91), one at +150 (2.50), one at −200 (1.50). Multiplied out, the combined decimal odds are 7.159 — so the $100 returns $715.91, a $615.91 profit at combined odds of +616. Every added leg multiplies the payout, and multiplies the difficulty right along with it.
What happens when a leg pushes
A push — the game lands exactly on the spread or total, or gets cancelled — doesn’t kill your parlay. The book simply removes that leg and recalculates the ticket as if it were never there: a three-leg parlay with one push pays as a two-legger. In the example above, if the +150 leg pushes, the ticket becomes 1.909 × 1.50 = 2.86, and the same $100 now returns $286.36. The Win / Push / Loss buttons on each leg let you settle your actual ticket the way the book will.
How a round robin works
Round robin mode does the same thing across many tickets at once: your picks become every possible smaller parlay, each staked separately, so one loss only sinks the tickets that contained it. Four picks ‘by 2s’ makes six two-leg tickets — at $10 each that’s $60 in play, and even with one losing pick, three tickets still cash.
Take the same three picks from the example above — −110, +150, −200 — plus one more at −110, played by 2s at $10 a ticket: six tickets, $60 in play, and a maximum payout of $226.67 if all four win. If the +150 pick loses, the three tickets that didn’t include it still pay — $93.72 back on the $60. A pushed pick drops out of each ticket individually, exactly like a straight-parlay push: a two-leg ticket with one pushed pick settles as a single bet on its other leg.
A round robin doesn’t beat the book’s margin — every ticket still carries it — but it reshapes the risk: you trade a smaller maximum payout for tickets that survive a miss. Flip the calculator above to Round robin mode to build one from your own picks.
The break-even number
Every set of odds implies a probability: 1 divided by the decimal odds. The +616 parlay above implies 14.0% — that’s how often the ticket has to hit, long-run, just to break even.
Here’s the honest part most calculators skip: each leg’s price carries the book’s margin, and a parlay multiplies those margins together. Ten legs at −110 pays +64,208 — but ten coin flips land together only about once in a thousand tries. The gap between what a parlay pays and what it’s truly worth grows with every leg you add. That’s why we treat parlays as entertainment and size them small — discipline is the edge most bettors overlook.
