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Odds converter

Type a price in any format. The other three update as you type.

e.g. 2.50

e.g. 6/4 or evens

e.g. +150 or −120

Margin included

How the formats relate

All four describe the same thing: how much a winning bet pays. Decimal odds are the total return per unit staked, stake included. Fractional odds are the profit per unit staked. American odds are the profit on a 100 stake when positive, or the stake needed to win 100 when negative.

decimal = fractional + 1 American +A → decimal = 1 + A / 100 American −A → decimal = 1 + 100 / A implied probability = 1 / decimal

So 6/4 is 1.5 + 1 = 2.50 in decimal, +150 in American, and implies a 40% chance.

Implied probability includes the bookmaker's margin, which is why the outcomes of one market add up to more than 100%. To get the fair price, use the no-vig calculator.

Common odds

DecimalFractionalAmericanImplied
1.251/4−40080.00%
1.501/2−20066.67%
1.804/5−12555.56%
1.9110/11−11052.36%
2.001/1 (evens)+10050.00%
2.1011/10+11047.62%
2.506/4+15040.00%
3.002/1+20033.33%
4.003/1+30025.00%
5.004/1+40020.00%
6.005/1+50016.67%
11.0010/1+10009.09%

FAQ

Odds format questions

Which odds format should I use?
Whichever your bookmaker shows, but decimal is the easiest to work with. The number already includes your stake, so 2.50 means a €10 bet returns €25. It also makes arbitrage, no-vig and Kelly maths simple, which is why every calculator on this site uses decimal odds.
What does a minus sign mean in American odds?
Negative American odds show how much you need to stake to win 100, so −150 means staking 150 to win 100 (decimal 1.667). Positive odds show what a 100 stake wins, so +150 means a 100 stake wins 150 (decimal 2.50). Anything at or near +100 and −100 is roughly an even-money bet.
Why does 1.91 come out as 10/11?
Bookmakers' fractions are rounded. 10/11 is exactly 1.909 in decimal, which most sites display as 1.91. The converter picks the closest simple fraction a bookmaker would use and marks the result as approximate (≈) when it isn't exact.
Why do the implied probabilities for a market add up to more than 100%?
Because the odds include the bookmaker's margin. In a fair market the probabilities would add up to exactly 100%; the extra is the bookmaker's edge, also called the overround or vig. The no-vig calculator removes it and shows the fair odds.
Is implied probability the real chance of winning?
No. It's the chance the price implies, including the bookmaker's margin. A price only tells you what the bookmaker is willing to pay. Comparing it with a margin-free price from a sharp bookmaker or exchange is how value bettors decide whether a price is too generous.

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