Odds Converter (Fractional, Decimal & American)
Use our odds converter to instantly convert betting odds between fractional, decimal, and American formats. The tool also shows implied probability and returns, allowing you to compare prices accurately across different bookmakers.
Odds conversion does not change the value of a bet — it simply translates how probability is expressed. This makes an odds converter essential when comparing markets, assessing prices, or analysing bookmaker margins.
Odds Converter
Values update automatically as you type
What Is an Odds Converter?
An odds converter translates betting odds between different formats — fractional, decimal, and American — without changing the underlying probability of the outcome.
Different regions use different odds formats, which can make it difficult to compare prices across bookmakers. An odds converter removes that friction by standardising odds instantly.
For example, the following odds all represent the same bet: 5/2 (fractional), 3.50 (decimal), and +250 (American).
Odds Conversion Table (With Implied Probability & Returns)
Compare fractional, decimal and American odds alongside implied probability and total return from a £10 stake. Total return includes your original stake.
| Fractional | Decimal | American | Implied Probability | £10 Total Return |
|---|---|---|---|---|
| 1/100 | 1.01 | -10000 | 99.0% | £10.10 |
| 1/50 | 1.02 | -5000 | 98.0% | £10.20 |
| 1/33 | 1.03 | -3333 | 97.1% | £10.30 |
| 1/25 | 1.04 | -2500 | 96.2% | £10.40 |
| 1/20 | 1.05 | -2000 | 95.2% | £10.50 |
| 1/16 | 1.06 | -1667 | 94.3% | £10.60 |
| 1/14 | 1.07 | -1429 | 93.5% | £10.70 |
| 1/13 | 1.08 | -1250 | 92.6% | £10.80 |
| 1/11 | 1.09 | -1111 | 91.7% | £10.90 |
| 1/10 | 1.10 | -1000 | 90.9% | £11.00 |
| 1/9 | 1.11 | -900 | 90.0% | £11.10 |
| 1/7 | 1.14 | -714 | 87.7% | £11.40 |
| 1/6 | 1.17 | -600 | 85.7% | £11.70 |
| 1/5 | 1.20 | -500 | 83.3% | £12.00 |
| 1/4 | 1.25 | -400 | 80.0% | £12.50 |
| 1/3 | 1.33 | -300 | 75.0% | £13.30 |
| 2/5 | 1.40 | -250 | 71.4% | £14.00 |
| 1/2 | 1.50 | -200 | 66.7% | £15.00 |
| 4/7 | 1.57 | -175 | 63.6% | £15.70 |
| 4/6 | 1.67 | -150 | 60.0% | £16.70 |
| 4/5 | 1.80 | -125 | 55.6% | £18.00 |
| 10/11 | 1.91 | -110 | 52.4% | £19.10 |
| 1/1 (Evens) | 2.00 | +100 | 50.0% | £20.00 |
| 11/10 | 2.10 | +110 | 47.6% | £21.00 |
| 6/5 | 2.20 | +120 | 45.5% | £22.00 |
| 5/4 | 2.25 | +125 | 44.4% | £22.50 |
| 7/5 | 2.40 | +140 | 41.7% | £24.00 |
| 6/4 | 2.50 | +150 | 40.0% | £25.00 |
| 7/4 | 2.75 | +175 | 36.4% | £27.50 |
| 2/1 | 3.00 | +200 | 33.3% | £30.00 |
| 5/2 | 3.50 | +250 | 28.6% | £35.00 |
| 3/1 | 4.00 | +300 | 25.0% | £40.00 |
| 7/2 | 4.50 | +350 | 22.2% | £45.00 |
| 4/1 | 5.00 | +400 | 20.0% | £50.00 |
| 9/2 | 5.50 | +450 | 18.2% | £55.00 |
| 5/1 | 6.00 | +500 | 16.7% | £60.00 |
| 6/1 | 7.00 | +600 | 14.3% | £70.00 |
| 7/1 | 8.00 | +700 | 12.5% | £80.00 |
| 8/1 | 9.00 | +800 | 11.1% | £90.00 |
| 9/1 | 10.00 | +900 | 10.0% | £100.00 |
| 10/1 | 11.00 | +1000 | 9.1% | £110.00 |
| 12/1 | 13.00 | +1200 | 7.7% | £130.00 |
| 15/1 | 16.00 | +1500 | 6.2% | £160.00 |
| 20/1 | 21.00 | +2000 | 4.8% | £210.00 |
| 25/1 | 26.00 | +2500 | 3.8% | £260.00 |
| 33/1 | 34.00 | +3300 | 2.9% | £340.00 |
| 50/1 | 51.00 | +5000 | 2.0% | £510.00 |
| 100/1 | 101.00 | +10000 | 1.0% | £1,010.00 |
| 1000/1 | 1001.00 | +100000 | 0.1% | £10,010.00 |
Odds Formats Explained
Decimal Odds
Decimal odds show your total return (including stake) per £1 staked.
A £10 bet at 2.40 returns £24 in total.
Fractional Odds
Fractional odds show profit relative to stake.
Odds of 7/4 mean £7 profit for every £4 staked.
American Odds
Positive odds show profit on a $100 stake.
Negative odds show how much you must stake to win $100.
No format is better than another — they simply express the same probability in different ways.
Implied Probability Explained
Implied probability represents the chance of an outcome occurring based on the odds offered by a bookmaker. It allows bettors to compare prices objectively, regardless of odds format.
For example, decimal odds of 2.00 imply a 50% chance of success.
Understanding implied probability helps bettors assess price quality, compare bookmakers, and identify potential value.
Odds, Margin & Bookmaker Pricing
Bookmakers build profit into odds through margin (also known as overround). This is calculated by adding the implied probabilities of all outcomes in a market.
When the total exceeds 100%, the excess represents the bookmaker’s margin. Higher totals mean worse prices for bettors.
Using an odds converter makes it easier to spot inflated margins and compare prices across bookmakers objectively.
Identifying Value Using Implied Probability
A bet has value when your estimated probability of an outcome is higher than the bookmaker’s implied probability.
This approach focuses on price quality rather than short-term results. It is commonly used by long-term and professional bettors.
Odds format is irrelevant once converted — probability is the common language behind all prices.
Using an Odds Converter With Accumulators
Accumulator bets require odds to be multiplied together, which is easiest when using decimal format.
An odds converter allows you to: convert odds to decimal, calculate combined returns, and convert back to your preferred format.
This reduces compounding errors and improves accuracy, especially on multi-leg bets.
Responsible Gambling Notice
Odds converters are informational tools. They do not increase your chances of winning or predict outcomes.
Always bet within your limits, understand variance, and avoid chasing losses.
FAQs – Odds Converter
An odds converter changes betting odds between fractional, decimal, and American formats without altering the underlying probability.
Odds formats developed regionally. UK bookmakers use fractional odds, European markets prefer decimal odds, and US sportsbooks use American odds.
No. Converting odds only changes how they are displayed. The probability and potential value of the bet remain the same.
Implied probability shows the chance of an outcome based on the odds offered, including the bookmaker’s margin.
Yes. Odds converters use standard mathematical formulas and provide accurate conversions across all supported formats.