Fractional to Decimal Odds Converter
Use this fractional to decimal odds converter to translate any UK-style fractional price into the decimal format used by Pinnacle, Betfair, and most non-US sportsbooks. Decimal odds make payout math trivial: stake × decimal = total return.
The formula
Decimal = (Numerator ÷ Denominator) + 1Example: 5/2 → (5 ÷ 2) + 1 = 3.50. 3/1 → 3 + 1 = 4.00.For favorites the fraction is less than 1/1: 1/2 → 0.5 + 1 = 1.50. 4/5 → 0.8 + 1 = 1.80.
Reference table
Common fractional lines and their decimal, fractional, and implied probability values.
| Fractional | Decimal | Probability |
|---|---|---|
| 1/5 | 1.20 | 83.3% |
| 1/2 | 1.50 | 66.7% |
| 67/100 | 1.67 | 59.9% |
| 1/1 | 2.00 | 50.0% |
| 3/2 | 2.50 | 40.0% |
| 2/1 | 3.00 | 33.3% |
| 3/1 | 4.00 | 25.0% |
| 4/1 | 5.00 | 20.0% |
| 5/1 | 6.00 | 16.7% |
| 9/1 | 10.00 | 10.0% |
Frequently Asked Questions
Why convert fractional to decimal?
Decimal is the universal format outside the US: Pinnacle, Betfair (exchange), Smarkets, and most non-UK sportsbooks default to decimal. Decimal odds also make payout math instant (stake × decimal = total return).
Why does 1/1 equal decimal 2.00?
1/1 ("evens") means 1 unit profit per 1 unit staked: even money. Decimal 2.00 doubles your stake. Both are 50% implied probability.
Can the calculator handle mixed numbers like 1 1/2?
No, enter pure fractions like "3/2" or "5/4". Convert any mixed number to an improper fraction first (1 1/2 = 3/2).