Odds Converter
Our free odds converter turns fractional odds into decimal and American odds, shows the implied probability, and works out the return on your stake.
Fractional odds are rounded to the nearest common price. Implied probability is 1 divided by the decimal odds, before the bookmaker’s margin is removed.
How the odds formats compare
Fractional odds (5/2) show profit against stake: win £5 for every £2 staked. They’re the traditional UK format, especially in racing.
Decimal odds (3.50) show the total return per £1, including your stake. Betting exchanges and most apps can show them.
American odds (+250 or -200) show the profit on a $100 stake for positive numbers, or the stake needed to win $100 for negative numbers.
What implied probability tells you
Implied probability is the chance the price suggests, worked out as 1 divided by the decimal odds. Odds of 3.50 imply about 28.6%. Add up the implied probabilities of every outcome in a market and the total is over 100%. The excess is the bookmaker’s margin, so a market with a lower total offers better value.
For more on how odds and margins work, read our guide to how free bets work or compare live prices on our odds page.
Evens (1/1) is 2.00 in decimal odds and +100 in American odds. A £10 bet returns £20. Some decimal prices don’t convert to a neat fraction, so the converter shows the nearest common fractional price.What is evens in decimal odds?
Why doesn't the fraction match exactly?
18+ only. The converter is for guidance; your bookmaker’s settlement rules always apply.