Odds Converter
Convert decimal, fractional and American odds — and read the true implied probability.
| Decimal | Fractional | American | Implied |
|---|---|---|---|
| 1.10 | 1/10 | −1000 | 90.91 % |
| 1.20 | 1/5 | −500 | 83.33 % |
| 1.25 | 1/4 | −400 | 80.00 % |
| 1.33 | 33/100 | −303 | 75.19 % |
| 1.40 | 2/5 | −250 | 71.43 % |
| 1.50 | 1/2 | −200 | 66.67 % |
| 1.57 | 57/100 | −175 | 63.69 % |
| 1.67 | 67/100 | −149 | 59.88 % |
| 1.75 | 3/4 | −133 | 57.14 % |
| 1.83 | 83/100 | −120 | 54.64 % |
| 1.91 | 91/100 | −110 | 52.36 % |
| 2.00 | 1/1 | +100 | 50.00 % |
| 2.10 | 11/10 | +110 | 47.62 % |
| 2.20 | 6/5 | +120 | 45.45 % |
| 2.38 | 69/50 | +138 | 42.02 % |
| 2.50 | 3/2 | +150 | 40.00 % |
| 2.75 | 7/4 | +175 | 36.36 % |
| 3.00 | 2/1 | +200 | 33.33 % |
| 3.50 | 5/2 | +250 | 28.57 % |
| 4.00 | 3/1 | +300 | 25.00 % |
| 5.00 | 4/1 | +400 | 20.00 % |
| 6.00 | 5/1 | +500 | 16.67 % |
| 8.00 | 7/1 | +700 | 12.50 % |
| 11.00 | 10/1 | +1000 | 9.09 % |
| 21.00 | 20/1 | +2000 | 4.76 % |
The prices books actually print, in all three formats. Implied probability includes the margin — it is what the odds say, not what is true.
How it works
Decimal odds show the total return per 1 unit staked, stake included (2.00 returns 2). Fractional odds show profit only (5/2 means 2.5 profit per 1 staked). American odds show the profit on a 100 stake for underdogs (+150) or the stake needed to win 100 for favourites (−110).
Implied probability is the break-even win chance baked into the price: 1 ÷ decimal odds. If your own honest estimate is higher than the implied probability, the bet is +EV. Because of the bookmaker margin, the implied probabilities of all outcomes add up to more than 100%.
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How the Odds Converter works
An odds converter translates the same betting price between the three formats bookmakers use — decimal, fractional and American (moneyline) — and shows the implied probability behind it. This free odds converter does it instantly and, given a stake, also returns your total payout and net profit.
The three odds formats
Decimal odds (popular in Europe) show the total return per 1 unit staked, including your stake: 2.50 returns 2.50 for every 1 risked. Fractional odds (UK) show profit only, so 6/4 is the same as 2.50 decimal. American odds (US) use +150 to mean '150 profit on a 100 stake' and −110 to mean 'stake 110 to win 100'.
All three describe the same thing, just scaled differently. Converting to decimal first makes every other format and the probability a one-step calculation.
Implied probability and value
Implied probability is simply 1 ÷ decimal odds. Odds of 2.00 imply a 50% break-even chance, 1.50 imply 66.7%, and 5.00 imply 20%. This is the number that matters: if your own honest estimate of an outcome is higher than the implied probability, the bet has positive expected value (+EV).
Add up the implied probabilities of every outcome in a market and you will get more than 100%. That excess is the bookmaker's margin (the 'vig' or 'overround') — the built-in edge you are paying on every bet.
How to use this converter
Pick the format you have, type the value, and read every other format plus the implied probability live. Enter an optional stake to see the exact payout and profit in your currency. It works for sports betting, exchange prices and any fixed-odds market.
Three separate bets and one winner: why the odds format matters
For three separate equal cash stakes S with only one winner at decimal odds D, total return is S × D and net profit is S × D − 3 × S. The losing stakes still count toward the total cost.
American odds +1500 convert to decimal 16.00. Three stakes of 10 with one winner return 160 and give net profit 130. Decimal odds 1500.00 would instead return 15,000 and give profit 14,970. Set the format explicitly; this converter calculates one winning bet at a time. For equal-return allocations between mutually exclusive selections, use Dutching Calculator.
Converting odds without changing probability
Decimal 2.50, fractional 3/2 and American +150 describe the same gross return: a stake of 100 returns 250 on a win, including the stake. Their implied probability is 1/2.50 = 40%. This conversion does not remove bookmaker margin or establish a true win probability.
FAQ
How do I convert decimal odds to probability?expand_more
Divide 1 by the decimal odds. For example 1 ÷ 2.50 = 0.40, so the implied probability is 40%.
What does +150 mean in American odds?expand_more
A positive American number is the profit on a 100 stake: +150 returns 150 profit (250 total) for every 100 risked, equal to decimal 2.50 or fractional 6/4.
What does −110 mean?expand_more
A negative American number is how much you must stake to win 100. −110 means risk 110 to win 100, which is decimal 1.91 — the standard price on a balanced point-spread bet.
Why do the probabilities add up to more than 100%?expand_more
The extra is the bookmaker's margin (overround). It is how the book makes money and why beating the implied price requires a genuine edge.
Are decimal odds the profit multiplier?expand_more
It multiplies gross return, including the stake. Net profit on a winning bet is stake × (decimal odds − 1). A losing bet normally loses the stake.
Why do implied probabilities add up to more than 100%?expand_more
A bookmaker's prices usually include an overround. Use the no-vig calculator to inspect margin-removal methods; even no-vig probabilities remain estimates rather than verified true chances.