American (+150 / -200)

Positive = profit on a 100-unit stake. Negative = stake needed to win 100. Standard at US sportsbooks.

Total return per 1 unit staked, stake included. Multiply leg decimals together to get combined parlay decimal.

Net profit per unit staked. 3/2 means risk 2 to win 3. Common in UK and horse racing.

Net profit per 1 unit staked, stake excluded. Decimal odds minus 1.

Indonesian (1.50 / -2.00)

American odds divided by 100. Common across Indonesian, Singaporean, and broader Asian sportsbooks.

Capped between -1 and 1. Positive = underdog, negative = favourite. Common across Malaysian markets.

Implied probability (40%)

Break-even win rate at the offered odds. Multiplied across legs gives the parlay's combined implied probability.

Parlay Calculator: Combine Bets, See Combined Odds and Payout

Parlay Calculator

Combine multiple bets into one wager. All legs must win for the parlay to pay.

Stake Odds format

Parlay legs

Combined odds (decimal) -

Combined odds (American) -

Total payout -

Net profit -

Implied probability -

About the Parlay Calculator

A parlay (also called an accumulator, multi, or combo) is a single bet that combines two or more separate selections. All selections must win for the parlay to pay out. In exchange for that all-or-nothing risk, the payout scales multiplicatively. a 4-leg parlay at −110 each pays around 12-to-1 instead of the roughly 1-to-1 you'd get on each single bet.

This calculator multiplies the decimal odds of every leg you enter, then applies your stake to show the combined payout, net profit, and implied probability of the parlay hitting. Use it to size parlay stakes, compare parlay prices across books, or see how adding one more leg changes the math.

Worked examples

100-unit stake on common parlay configurations (all legs at −110, i.e. decimal 1.9091):

Legs	Combined decimal	Combined American	Total payout	Net profit	Implied %
2	3.6446	+264	364.46	264.46	27.44
3	6.9579	+596	695.79	595.79	14.37
4	13.2833	+1228	1,328.33	1,228.33	7.53
5	25.3591	+2436	2,535.91	2,435.91	3.94
6	48.4127	+4741	4,841.27	4,741.27	2.07
10	643.08	+64208	64,308.16	64,208.16	0.16

Why parlays favour the house

Every single bet at −110 carries roughly a 4.5% house edge. When you parlay legs together, those edges compound. A 4-leg parlay at −110s carries an effective hold close to 18%. much higher than the 4.5% on each individual leg. The math is correct and the payouts are real, but the bet's expected value is worse than placing the same legs as singles. Parlays make sense when you have positive expected value on every leg, or when the entertainment of a long-shot ticket is worth the negative EV.

A correlated parlay (e.g. NFL favourite to win + same team to cover the spread) is a different case. the legs are not independent and most books either disallow it or recompute the price. The math here assumes independent legs, which is the standard sportsbook treatment.

Odds format reference

American (+150 / −200): Positive = profit on a 100-unit stake. Negative = stake needed to win 100. Standard at US sportsbooks.
Decimal (2.50): Total return per 1 unit staked, stake included. Multiply leg decimals together to get combined parlay decimal.
Fractional (3/2): Net profit per unit staked. 3/2 means risk 2 to win 3. Common in UK and horse racing.
Hong Kong (1.50): Net profit per 1 unit staked, stake excluded. Decimal odds minus 1.
Indonesian (1.50 / −2.00): American odds divided by 100. Common across Indonesian, Singaporean, and broader Asian sportsbooks.
Malay (0.50 / −0.67): Capped between −1 and 1. Positive = underdog, negative = favourite. Common across Malaysian markets.
Implied probability (40%): Break-even win rate at the offered odds. Multiplied across legs gives the parlay's combined implied probability.