Results appear here as you type.
For information and entertainment only — not betting, financial or legal advice. Results are estimates based on your inputs.
How the Odds Converter works
Choose the format you are starting from, type the odds and the converter shows the same price in every other format, plus the probability the odds imply. Decimal odds show your total return per 1 staked; fractional odds show profit relative to stake; American odds show profit on 100 (positive) or the stake needed to win 100 (negative).
Formula
- Implied probability = 1 ÷ decimal odds
- Fractional = decimal − 1 (as a fraction)
- American: decimal ≥ 2 → (decimal − 1) × 100; decimal < 2 → −100 ÷ (decimal − 1)
Worked example
Fractional 5/2 equals decimal 3.50, American +250 and an implied probability of 28.6% (1 ÷ 3.5).
Frequently asked questions
What is the difference between decimal and fractional odds?
Decimal odds include your stake in the return (3.50 returns 3.50 for every 1 staked). Fractional odds describe profit only (5/2 means 5 profit for every 2 staked).
Why do two odds formats give a slightly different implied probability?
They do not — every format converts to the same decimal price first. Small differences only come from rounding fractions.
Play responsibly
Calculators describe maths, not outcomes. Gambling is for adults aged 18+ and can be addictive — set limits and never stake money you cannot afford to lose.