Odds Converter and Payout Calculator
Convert between decimal, fractional and American odds instantly, with the implied probability, the payout on your stake and the traditional betting fraction a UK bookmaker would actually display.
European format — your total return per £1 staked. E.g. 2.50 means £2.50 back.
UK format — your profit relative to stake. E.g. 3/2 means £3 profit per £2 staked.
US format — positive shows profit on $100, negative shows stake needed to win $100.
Implied Probability
40.0%
Stake
Potential Payout
£250.00
Profit: £150.00
Exact Fraction vs Bookmaker Price
Exact Fraction
3/2
The arithmetically correct fraction for this decimal price.
Nearest Bookmaker Price
6/4 (2.50)
This price sits exactly on the traditional fraction ladder.
How to Use the Odds Converter
Enter a value in any of the three formats and the other two update automatically. The implied probability tells you the likelihood of the outcome as suggested by the odds — useful for spotting value when your own assessment differs from the price on offer.
Decimal Odds (European)
The most straightforward format. Your total return equals your stake multiplied by the decimal odds. A £10 bet at 2.50 returns £25.00, of which £15.00 is profit. Decimal odds always include the stake in the return, which is why they never fall below 1.00.
Fractional Odds (UK)
The traditional UK format shows profit relative to stake: 3/2 means £3 profit for every £2 staked. To convert to decimal, divide the fraction and add 1 (3 ÷ 2 + 1 = 2.50). The catch is that fractions are not continuous — bookmakers price to a fixed ladder of steps, so an exact conversion and a board price can disagree slightly. This page shows both rather than quietly picking one.
American Odds (Moneyline)
Positive values (+150) show profit on a $100 stake. Negative values (−200) show how much you need to stake to win $100. Positive odds mark an underdog, negative odds a favourite, and the format flips at evens, which is +100 exactly.
How to Calculate a Moneyline Payout
For a positive line, the profit is your stake multiplied by the odds divided by 100. For a negative line, it is your stake multiplied by 100 divided by the odds, ignoring the minus sign. Add the stake back to get the payout. On a £10 stake:
- +150: 10 × 150 ÷ 100 = £15.00 profit, £25.00 payout (decimal 2.50).
- −200: 10 × 100 ÷ 200 = £5.00 profit, £15.00 payout (decimal 1.50).
- −110: 10 × 100 ÷ 110 = £9.09 profit, £19.09 payout (decimal 1.91).
Type the line into the American box above and the payout panel does the same sum for any stake, in any of the three formats.
Implied Probability and the Bookmaker's Margin
Implied probability is 1 ÷ decimal odds × 100. At 2.00 it is 50%. Add up the implied probabilities of every outcome in a market and the total exceeds 100%: the excess is the bookmaker's margin, the edge built into the prices. The Bookmaker Margin Calculator measures it for any market, and the betting glossary explains the vocabulary around it.
Common Odds at a Glance
| Fractional | Decimal | American | Implied Probability |
|---|---|---|---|
| 1/4 | 1.25 | −400 | 80.0% |
| 1/2 | 1.50 | −200 | 66.7% |
| 10/11 | 1.91 | −110 | 52.4% |
| Evens | 2.00 | +100 | 50.0% |
| 6/4 | 2.50 | +150 | 40.0% |
| 2/1 | 3.00 | +200 | 33.3% |
| 5/1 | 6.00 | +500 | 16.7% |
| 10/1 | 11.00 | +1000 | 9.1% |
| 33/1 | 34.00 | +3300 | 2.9% |
Once the price is converted, the Bet Calculator works out the return on any of 19 bet types, and the Each-Way Calculator handles the place half of a racing bet, where the fraction is applied a second time.
Frequently Asked Questions
How do I convert decimal odds to fractional odds?
Subtract 1 from the decimal price and express the result as a fraction. Decimal 2.50 gives 1.50, which is 3/2. Going the other way, divide the fraction and add 1. The subtraction matters: decimal odds include your stake, fractional odds do not.
Why does the exact fraction differ from the bookmaker price?
Bookmakers price to a traditional ladder of fractions — 1/5, 2/9, 1/4, 4/11 and so on — rather than to every fraction that exists. A decimal price of 1.36 is exactly 9/25, but no board shows 9/25, so it appears as 4/11 (1.3636). The difference is real money on a big stake, which is why this page reports both figures instead of rounding silently.
What do American odds of +150 and −200 mean?
+150 means a 100-unit stake wins 150 in profit, a price of 2.50 in decimal. −200 means you must stake 200 to win 100, a price of 1.50. Anything with a plus sign is an underdog, anything with a minus sign is a favourite, and evens is written +100.
How do I calculate a moneyline payout?
For a positive line, divide the odds by 100 and multiply by your stake to get the profit: £10 at +150 wins £15, a £25 payout. For a negative line, divide 100 by the odds, ignoring the minus sign, and multiply by your stake: £10 at −110 wins £9.09, a £19.09 payout. The payout always includes the stake.
Why do the implied probabilities add up to more than 100%?
Because the prices contain the bookmaker's margin. In a fair two-way market both outcomes would be 2.00 and the probabilities would total exactly 100%. Real prices of 1.91 and 1.91 total 104.7%, and that 4.7% is the margin. The higher the total, the worse the value on offer.
Do decimal and fractional odds ever pay differently?
No — they are two ways of writing the same price, and a bet is settled on the price you took, not the format it was shown in. The only practical difference is rounding: a bookmaker who prices in fractions has to land on a ladder step, so the decimal equivalent can look untidy.
Converting a price does not make it a good bet — the margin is built into every format equally. Set a budget before you stake and never chase losses. 18+. If gambling stops being fun, see our responsible gambling resources.