Odds calculator
Convert decimal, fractional or American odds to the other formats and check implied probability. The result represents the same mathematical relationship in different notations.
Conversion
- Decimal
- 2.5
- Fractional
- 3/2
- American
- +150
- Implied probability
- 40%
Implied probability is a mathematical equivalent of odds. It is not a prediction and does not account for a bookmaker's margin or guarantee an outcome.
How to convert odds
Decimal odds already include the initial unit. To get fractional odds, subtract 1 and express the result as a fraction. Implied probability is 100 divided by decimal odds.
Positive American odds show the return above 100; negative odds show the amount needed to win 100. The formats describe the same mathematical relationship.
Example: converting odds of 2.50
- Enter decimal odds of 2.50.
- Subtract 1: 2.50 − 1 = 1.50, equal to the fraction 3/2.
- Calculate 100 ÷ 2.50 for implied probability.
Result: 2.50 decimal equals 3/2 fractional, +150 American and 40% implied probability.