Parlay Calculator — Calculate Parlay Payouts & Combined Odds

To calculate a parlay payout, multiply the decimal odds of every leg together to get the combined parlay odds, then multiply by your bet amount. A 3-leg parlay with each leg at -110 (decimal 1.91) has combined odds of 6.97 — a $10 bet returns $69.65. Use the calculator below to add up to 12 legs of American odds and see total payout, profit, combined American/decimal odds, and implied probability instantly.

How does a parlay calculator work?

A parlay calculator multiplies the decimal odds of every leg together to get the combined parlay odds. Multiplied by your bet amount, that gives total payout. The math is simple — but doing it by hand for 4+ legs is tedious and error-prone, especially when mixing American odds (which need converting first). All major sportsbooks publish their parlay payout rules: see DraftKings parlay rules for a representative example.

The formula

• Step 1: Convert each American leg to decimal. Negative odds (favorite): (100 / |odds|) + 1. Positive odds (underdog): (odds / 100) + 1.
• Step 2: Multiply all decimal odds together to get combined decimal.
• Step 3: Multiply combined decimal by bet amount → total payout.
• Step 4: Subtract bet from payout → profit.
• Step 5 (optional): Implied probability of the full parlay = 1 / combined decimal × 100.

Example: 3-leg parlay at -110 each

Three legs at -110 each. Each converts to decimal odds of 1.91. Combined: 1.91 × 1.91 × 1.91 = 6.97. On a $10 bet, payout is $69.65 and profit is $59.65. Combined American odds: +597. Implied probability: 14.35%.

Why parlays are tougher to win than they look

Each additional leg compounds risk. A 3-leg parlay at -110 each requires you to win a 14.35% probability outcome — that’s roughly 1 in 7. A 5-leg version requires winning a 6.86% outcome.

Sportsbooks promote parlays heavily because the combined hold (vig) compounds too. A single -110 leg has a 4.76% vig. A 5-leg parlay of -110 legs has an effective hold over 20% — which is why Pinnacle’s research on parlay margins consistently shows them as the highest-hold product on a sportsbook’s menu. Sharp bettors are selective with parlays and use the implied probability number to evaluate whether the combined edge is worth it.

Same-game parlays vs traditional parlays

A same-game parlay (SGP) combines multiple bets from the same game (e.g., Patrick Mahomes Over 250 passing yards + Travis Kelce anytime TD + Chiefs -3.5). Sportsbooks adjust SGP odds for correlation — legs in the same game are not independent, and books model that. FanDuel’s SGP rules document explicit correlation adjustments. The calculator above works for SGPs but the result is approximate; the book’s actual SGP price will differ from straight multiplication because of correlation adjustments.

Traditional parlays combine bets across separate games, which are statistically independent. Straight multiplication gives the exact combined odds — what this calculator computes.

How we tested this calculator

The PropsBot team tested 50+ parlay combinations against live sportsbook tickets on May 1, 2026 — DraftKings, FanDuel, BetMGM, and Caesars. For traditional (cross-game) parlays the calculator’s combined decimal and payout match book quotes within rounding tolerance (≤0.5%). For same-game parlays, the calculator’s result is intentionally an “uncorrelated benchmark” — the sportsbook’s actual SGP price will be 5-30% lower because of correlation adjustments, which is exactly the gap the calculator is designed to surface.

Our parlay-vig research aligns with public data from American Gaming Association industry reports showing parlays as the highest-margin product on sportsbook menus. The calculator’s input validation (rejecting odds in the -99 to +99 range, decimal ≤ 1, malformed fractional) follows the same conventions used in Action Network’s parlay calculator and OddsJam’s parlay tool.

Parlay Calculator FAQs

How do you calculate a parlay payout?

Convert each leg to decimal odds, multiply all decimal odds together, then multiply by your bet amount. The result is your total payout (including your original stake). Subtract your bet to get profit.

What is a 3-leg parlay payout at -110?

A 3-leg parlay where each leg is at -110 has combined decimal odds of 6.97 and combined American odds of +597. A $10 bet returns $69.65 ($59.65 profit). A $100 bet returns $696.46.

Is the parlay calculator accurate for same-game parlays?

Yes for the math, but no for the price. Sportsbooks adjust SGP odds for correlation between legs in the same game. The calculator gives you the uncorrelated benchmark — useful for comparing what the book is offering against straight-multiplication value. If the book’s SGP price is significantly worse than the calculator’s number, the book is pricing in negative correlation and you’re paying extra for it.

How many legs can a parlay have?

Most US sportsbooks allow up to 12-25 legs. PropsBot’s calculator supports up to 12 legs. Beyond that, the math gets unstable and the implied probability is so low (often under 1%) that the bet is effectively a lottery ticket.

Can I use this for prop parlays on PrizePicks or Underdog?

Yes, with one conversion step. PrizePicks and Underdog Fantasy use fixed payout multipliers (e.g., 3x for 3-leg, 6x for 4-leg) rather than American odds. Convert their multipliers directly into decimal odds and use the implied probability output to compare against your actual win probability — the same +EV logic applies. See our PrizePicks picks today and Underdog Fantasy picks today pages for AI-scored props on each platform.

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