Convert between decimal, fractional, and American odds instantly. Enter a value in any field and the others update automatically.
| Decimal | Fractional | American | Probability |
|---|---|---|---|
| 1.5 | 1/2 | -200 | 66.7% |
| 1.8 | 4/5 | -125 | 55.6% |
| 2.0 | 1/1 | +100 | 50.0% |
| 2.5 | 3/2 | +150 | 40.0% |
| 3.0 | 2/1 | +200 | 33.3% |
| 4.0 | 3/1 | +300 | 25.0% |
| 5.0 | 4/1 | +400 | 20.0% |
| 6.0 | 5/1 | +500 | 16.7% |
| 10.0 | 9/1 | +900 | 10.0% |
| 21.0 | 20/1 | +2000 | 4.8% |
Betting odds are displayed in three main formats worldwide. Decimal odds (e.g., 2.50) are the standard across Europe and Scandinavia, showing your total return per unit staked including the stake itself. Fractional odds (e.g., 3/2) are traditional in the UK and Ireland, showing profit relative to stake. American odds (e.g., +150 or -200) are used primarily in the United States, with positive numbers showing profit on a $100 bet and negative numbers showing how much you need to stake to profit $100.
All three formats express the same underlying information — the bookmaker's assessment of probability and payout — just presented differently. Converting between them is essential when comparing odds across international bookmakers.
Decimal to Fractional: Subtract 1 from the decimal odds. Decimal 2.50 becomes 1.50, or 3/2 as a fraction.
Decimal to American: If decimal odds are 2.00 or above, use (Decimal - 1) × 100 for the positive value. Decimal 3.00 = +200. If below 2.00, use -100 ÷ (Decimal - 1). Decimal 1.50 = -200.
Any format to Implied Probability: For decimal odds, divide 1 by the odds and multiply by 100. Odds of 2.00 imply a 50% chance (1 ÷ 2.00 = 0.50). This is key for assessing whether a bet offers value.
Every set of odds implies a probability. If you believe a team has a 60% chance of winning but the bookmaker's odds imply only 50%, you have found a value bet. Consistently finding value is the foundation of profitable betting.
Use this converter alongside our EV Calculator to assess whether specific bets are worth taking, and our Margin Calculator to see how much the bookmaker is charging you in hidden fees.
For most European and Scandinavian bettors, decimal odds are the clearest format. They make it easy to calculate returns (just multiply by your stake) and compare prices across bookmakers. If you are reading tipster content from the UK, you will encounter fractional odds, and American odds appear on US-focused sites. Having the ability to convert between all three ensures you never miss a value opportunity. For a deeper explanation of each format, see our Football Betting for Beginners guide.