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Type odds in any format and see the other formats instantly: decimal, fractional, American and implied probability. You can also check the bookmaker margin on a 1X2 or two-way market.
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| Decimal | Fractional | American | Implied % |
|---|---|---|---|
| 1.50 | 1/2 | -200 | 66.67% |
| 2.00 | 1/1 (evens) | +100 | 50.00% |
| 2.50 | 3/2 (6/4) | +150 | 40.00% |
| 3.00 | 2/1 | +200 | 33.33% |
| 5.00 | 4/1 | +400 | 20.00% |
Odds converter
Type in any one box; the others update.
Bookmaker margin
Enter 2 or 3 decimal prices for one market (e.g. 1X2).
Odds conversion table
| Decimal | Fractional | American | Implied % |
|---|---|---|---|
| 1.50 | 1/2 | -200 | 66.67% |
| 2.00 | 1/1 (evens) | +100 | 50.00% |
| 2.50 | 3/2 (often shown as 6/4) | +150 | 40.00% |
| 3.00 | 2/1 | +200 | 33.33% |
| 5.00 | 4/1 | +400 | 20.00% |
Worked example in naira
Odds of 6/4 are 2.50 in decimal and +150 in American. A ₦1,000 stake returns ₦2,500 (₦1,500 profit) if it wins. The implied probability is 100 ÷ 2.50 = 40%.
How the conversions work
- Fractional a/b to decimal: 1 + a ÷ b.
- American +A to decimal: 1 + A ÷ 100. American −A: 1 + 100 ÷ A.
- Implied probability: 100 ÷ decimal odds.
- Decimal to fractional: the nearest simple fraction (denominator up to 100), plus the usual bookmaker fraction where one matches, e.g. 3/2 is shown as 6/4.
- Bookmaker margin: overround % = (sum of 1 ÷ each price − 1) × 100. Fair odds remove the margin in proportion to each price.
FAQ
How do I convert fractional odds to decimal?
Divide the top number by the bottom number and add 1. 6/4 = 1 + 1.5 = 2.50.
What do American odds of -200 mean?
You stake ₦200 to win ₦100 profit. In decimal that is 1.50.
What is implied probability?
The chance the odds suggest: 100 ÷ decimal odds. 2.50 implies 40%. It includes the bookmaker margin.
What is the bookmaker margin (overround)?
The amount the implied probabilities of all outcomes add up to above 100 percent. It is the bookmaker’s built-in edge.
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Play responsibly
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