Three formats, one number
All three odds formats represent the same underlying probability — the format is just convention. UK punters prefer fractional, Europeans use decimal, US sportsbooks use American moneyline. Implied probability tells you what win-rate the bookmaker is pricing in.
How to use it
- 1Pick the format you have (fractional, decimal or American) and type the odds in.
- 2Read the converted values in the gold panel on the right — all three formats plus implied probability.
- 3Click any row in the reference table to load that price into the converter instantly.
Example: 5/1 in three formats
Fractional 5/1 = decimal 6.00 = American +500. The implied probability is 16.7% — the bookmaker is pricing this selection as roughly a 1-in-6 shot. A £10 bet returns £60 if it wins (£50 profit + £10 stake back).
Enter odds
Quick conversion table
| Fractional | Decimal | American | Probability |
|---|---|---|---|
| 1/5 | 1.20 | -500 | 83.3% |
| 1/4 | 1.25 | -400 | 80.0% |
| 1/3 | 1.33 | -300 | 75.2% |
| 1/2 | 1.50 | -200 | 66.7% |
| 4/6 | 1.67 | -150 | 59.9% |
| Evens | 2.00 | +100 | 50.0% |
| 6/4 | 2.50 | +150 | 40.0% |
| 2/1 | 3.00 | +200 | 33.3% |
| 3/1 | 4.00 | +300 | 25.0% |
| 5/1 | 6.00 | +500 | 16.7% |
| 10/1 | 11.00 | +1000 | 9.1% |
| 20/1 | 21.00 | +2000 | 4.8% |
| 50/1 | 51.00 | +5000 | 2.0% |
Click any row to load it into the converter.
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Hand-picked siblings of this calculator — natural next steps in the bet-type family.
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Reverse the calc — what price do you need at the bookmaker to hit a target return?
OpenBet Calculator
Once you know the price, calculate your potential return on any bet type.
OpenFrequently Asked Questions
Common questions
- Fractional (UK) — 5/1 means £5 profit for every £1 staked, plus your stake back. Decimal (European) — 6.00 means £6 total return per £1 (including stake). American (US) — +500 means $5 profit per $1, or -500 means you stake $5 to win $1. All three describe the same probability; the format is just convention.
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