Odds Converter
Free odds converter: type a decimal, fractional or American price, or a percentage, and see the same odds in every other format instantly.
On this page
Common odds table
| Decimal | Fractional | American | Implied % |
|---|---|---|---|
| 1.20 | 1/5 | -500 | 83.3% |
| 1.25 | 1/4 | -400 | 80.0% |
| 1.33 | 1/3 | -303 | 75.2% |
| 1.40 | 2/5 | -250 | 71.4% |
| 1.50 | 1/2 | -200 | 66.7% |
| 1.57 | 4/7 | -175 | 63.7% |
| 1.67 | 4/6 | -149 | 59.9% |
| 1.73 | 8/11 | -137 | 57.8% |
| 1.80 | 4/5 | -125 | 55.6% |
| 1.91 | 10/11 | -110 | 52.4% |
| 2.00 | 1/1 (evens) | +100 | 50.0% |
| 2.10 | 11/10 | +110 | 47.6% |
| 2.20 | 6/5 | +120 | 45.5% |
| 2.50 | 3/2 | +150 | 40.0% |
| 2.75 | 7/4 | +175 | 36.4% |
| 3.00 | 2/1 | +200 | 33.3% |
| 3.50 | 5/2 | +250 | 28.6% |
| 4.00 | 3/1 | +300 | 25.0% |
| 5.00 | 4/1 | +400 | 20.0% |
| 6.00 | 5/1 | +500 | 16.7% |
| 8.00 | 7/1 | +700 | 12.5% |
| 11.00 | 10/1 | +1000 | 9.1% |
This odds converter rewrites one price in every format at once: type into the Decimal, Fractional, American or Implied probability box and the other three update. Nigerian bookmakers quote decimal odds, so the tool earns its place when a tipster, a preview or a foreign site gives you a price in another format and you want to compare it with your slip.
How to convert odds with the four boxes
- Pick the box that matches what you have. A price like 11/4 goes in Fractional, +175 or −130 in American, 3.75 in Decimal.
- Type it in full. Use a slash for fractions and keep the plus or minus sign on American odds, because the sign changes the answer completely.
- Read the other three boxes. They fill in as you type, including the implied probability.
- Check the common odds table. The table under the boxes lists popular prices in all four formats for a quick lookup.
The formulas behind each conversion
Every conversion passes through decimal odds, because decimal is the easiest form to calculate with.
- Fractional to decimal: divide the top number by the bottom one, then add 1. 11/4 = 2.75 + 1 = 3.75.
- Decimal to fractional: subtract 1 and write what is left as a fraction. 1.80 leaves 0.80, which is 4/5.
- Plus American to decimal: 1 + the number ÷ 100. +175 gives 2.75.
- Minus American to decimal: 1 + 100 ÷ the number. −130 gives 1.769, shown as 1.77.
- Decimal to American: at 2.00 or above, (decimal − 1) × 100 with a plus sign; below 2.00, −100 ÷ (decimal − 1).
- Any format to percentage: 100 ÷ decimal odds.
Example A UK preview prices an away win at 5/2. In decimal that is 5 ÷ 2 + 1 = 3.50; in American it is (3.50 − 1) × 100 = +250; as a percentage it is 100 ÷ 3.50 = 28.57%. A US site’s −120 on the other side converts to 1 + 100 ÷ 120 = 1.83 in decimal, 5/6 as a fraction and 54.55% implied.
Fractional to decimal odds and back
Fractional odds show profit against stake: 4/6 means you win ₦4 for every ₦6 staked, so the decimal price is 4 ÷ 6 + 1 = 1.67. Turn it around to 6/4 and the price becomes 2.50, a completely different bet. That swap is the most common conversion error, so check that the larger number is on top for an underdog and on the bottom for a favourite.
American odds: plus and minus prices
American odds use 100 as the anchor. A plus price is the profit on a 100 stake (+150 means 150 profit, decimal 2.50). A minus price is what you must stake to make 100 profit (−200 means stake 200, decimal 1.50). Evens is +100, which equals 2.00 and 1/1. You will mostly meet these when reading NBA or NFL previews written for American readers.
Three quick checks let you sanity-test any conversion in your head. A decimal price below 2.00 is always a minus American price and a fraction with the smaller number on top. A decimal price above 2.00 is always a plus price and a fraction with the bigger number on top. And 2.00, 1/1 and +100 are the same evens bet, so a basketball favourite at −250 must be well under 2.00 (it is 1.40, or 71.4%).
Why some converted odds look rounded
Bookmakers never show fractions like 91/100. They use a ladder of familiar fractions, so the converter shows the nearest bookmaker form: 1.91 appears as 10/11 (exactly 1.909), and 2.50 appears in its lowest terms, 3/2, even though racing sites often print it as 6/4. The same goes the other way: −110 is 1.909, which rounds to 1.91.
Converting a price and converting it back can drift by 0.01. When you place a bet, the price shown on your bookmaker’s slip is the one that settles it, so use the converter for comparison, not for settling.
Where Nigerian punters meet each odds format
| Format | Where you see it | Same price |
|---|---|---|
| Decimal | Every Nigerian bookmaker slip | 2.75 |
| Fractional | UK horse racing, UK tipsters | 7/4 |
| American | US sports previews and sites | +175 |
| Percentage | Prediction models, stats sites | 36.4% |
All four cells in the last column describe the same bet. Seeing them together makes it easy to judge a tip quoted in fractions against the decimal price on your own slip.
Mistakes to avoid when you convert odds
- Dropping the +1. 6/4 is 2.50 in decimal, not 1.50.
- Reading a minus sign as long odds. In American format the minus marks the favourite; −200 is only 1.50.
- Treating the percentage as the true chance. It still contains the bookmaker’s margin. For margin-free figures use the fair odds calculator, and to see the size of that margin use the overround tool.
Once a price is in decimal, the betting odds calculator turns it into a Naira return, and the implied probability page explains the percentage in more depth. If the formats themselves are new to you, start with what the numbers on a betting slip mean, then browse the other betting tools.
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Frequently asked questions
4/6 converts to 1.67 in decimal (4 ÷ 6 + 1 = 1.667). In American format it is −150, and the implied probability is 60%. It is a favourite's price, so ₦6 staked wins ₦4 profit.
+200 equals 3.00 in decimal and 2/1 as a fraction. The implied probability is 33.3%. A plus sign always means an underdog price at 2.00 or longer, with the number showing the profit on a 100 stake.
Evens is 1/1 in fractional form, +100 in American and 2.00 in decimal, with an implied probability of 50%. You win the same amount you stake, so ₦1,000 at evens returns ₦2,000.
Bookmakers use a fixed ladder of familiar fractions such as 10/11, 5/6 and 4/5, so a decimal like 1.91 is shown as the nearest one, 10/11. The tiny gap is rounding, and the price on your slip is always the one used to settle.
Yes. Type the percentage in the implied probability box and the decimal, fractional and American boxes fill in. 25% becomes 4.00, 3/1 and +300. For the break-even side of percentages, see the probability calculator.