Fractional odds express profit relative to stake; decimal odds include the returned stake in the winning-return multiplier. To convert fractional a/b to decimal, divide a by b and add 1. To reverse the process, subtract 1 from the decimal price and express the result as a fraction.
Convert without losing the stake component
At 5/2, the profit ratio is 2.5 to 1. Adding 1 gives decimal odds of 3.50. A £2 winning cash stake therefore produces £5 profit and £7 total return. Fractional odds of 1/2 correspond to decimal 1.50, not 0.50.
For decimal 2.20, subtracting 1 gives 1.20, which is 6/5 in fractional form. The two formats describe the same underlying price when converted exactly; changing the display does not improve the offer.
Common equivalent prices
| Fractional | Decimal | Profit on a winning £2 cash single |
|---|---|---|
| 1/4 | 1.25 | £0.50 |
| 1/2 | 1.50 | £1 |
| 1/1 | 2.00 | £2 |
| 6/4 | 2.50 | £3 |
| 5/2 | 3.50 | £5 |
| 4/1 | 5.00 | £8 |
Source notes: 1.
Worked example: interpreting a minimum price
A hypothetical promotion requires minimum decimal odds of 1.80. Fractional 4/5 converts to 1.80 and meets that price threshold exactly, assuming the clause includes equality. Fractional 8/11 converts to approximately 1.7273, so it falls below the threshold.
That establishes only the price condition. It does not establish eligibility, qualifying funding or the correct market. The accepted price on the receipt is more useful than a later live quote.
Rounding and unusual prices
A decimal price need not map neatly to a familiar fractional label. A display can round the conversion, so use the recorded accepted odds for calculations and ask which value the operator uses if a threshold is close.
Do not round each leg early when calculating a multiple. Keep the accepted decimal values through multiplication and round the final currency amount according to the applicable rules. Formatting a price to two decimals can conceal small differences.
Prices are not promises
The return calculation is conditional on the bet winning and the relevant settlement rules. Odds also do not reveal an objective probability of success. Understanding conversion helps read terms accurately; it does not remove the possibility of losing the stake.
Common questions
Are even money and 1/1 the same?
Yes. Both correspond to decimal 2.00, giving a profit equal to the stake on an ordinary winning cash bet.
Should I add 1 again when using decimal odds?
No. Decimal odds already include the stake-return component for an ordinary winning cash bet.
Sources and editorial notes
Official source material consulted for this edition. Operator examples are dated illustrations, not a guarantee of current terms or personal eligibility. Worked examples are hypothetical.
Published by eLand, Lda. See our editorial policy. Report a correction.