Odds Conversion Betting Calculator
Decimal, fractional, American and implied probability.
How to Use This Calculator
- Pick your odds format from the toggle: Decimal, Fractional, or American
- Type the odds value into the input field
- Read the equivalent odds across all three formats, plus implied probability
Examples:
- Decimal: 2.50
- Fractional: 3/2
- American: +150 or -200
Formula
Decimal to Fractional: Fractional = Decimal - 1 (expressed as a fraction)
Decimal to American:
- If Decimal >= 2.00: American = (Decimal - 1) x 100
- If Decimal < 2.00: American = -100 / (Decimal - 1)
Implied Probability: 1 / Decimal Odds x 100%
Frequently Asked Questions
Decimal odds — what are they?
Decimal odds state total return per $1 staked, stake included. Odds of 2.50 return $2.50 for each $1 wagered, a $1.50 profit.
Define American odds.
American odds carry + or - signs. A positive figure (+150) gives profit on a $100 stake. A negative figure (-200) gives the stake required to profit $100.
How do fractional odds work?
Fractional odds such as 3/2 return $3 profit per $2 staked. The first number is profit; the second is the stake.
Implied probability — definition?
Implied probability restates odds as a percentage reflecting the bookmaker’s assessed likelihood of the outcome. Shorter odds map to higher implied probability.