By convention only a set of fractions are used in fractional odds betting markets. The set does not include exact mathematical equivalents to all possible decimal and American odds. We use the closet fraction that is used in betting markets.

1. Decimal To Fractional Odds Formula
2. Decimal Odds Calculator

For example, the exact mathematical equivalent of decimal odds 30 is fractional odds 29/1. However 29/1 is not used in betting markets, instead 30/1 is used, so that is what appears in this converter.

For an explanation of the odds types on this table see decimal, fractional and American odds. To find out what the numbers really represent see understand odds as probability with overround.

With decimal odds, you would instantly see that 1.61 is bigger than 1.57. 2.54, 2.56 or 2.58, which are all available on the Exchange before the next standard fraction of 2.6 (8/5). Decimal Odds Eg. 3.00 (equivalent of 2/1). Multiply the odds by the stake to work out the total return. For example a £100 bet which won at 3.00 will give a profit of £200 and a total return of £300.

The simple formular to convert from fraction odds to decimal is to divide the numerator (top number) by the denominator (bottom number) and add 1. The 1 represents the returned stake which is included in the decimal odds but not in the fraction odds. Example 1: Odds of 2/1, will be 2 divided by 1, which gives 2, then add 1 equals 3. The advantage of decimal odds Fractional odds can sometimes be confusing as the calculation can produce very large numbers. For example, where the decimal odds are 1.46, the fractional equivalent would be 23/50. In this case, it is much easier to calculate the return from a.

Convert odds between American, Decimal, and Fractional format using simple odds conversion formulas. Or, skip the math and use the odds converter instead!

Decimal to Fractional

Remove 1 from the decimal and convert to a fraction, then reduce to simplest form:

(decimal-1) -> convert to fraction

Examples:

1.75: 1.75 – 1 = .75 = 75/100 = 3/4
2.20: 2.20 – 1 = 1.20 = 120/100 = 6/5

Decimal to American

To convert a decimal of 2.00 or higher:

moneyline = (decimal – 1) *100

Examples:

2.00: (2.00 – 1)*100 = 1*100 = +100
3.35: (3.35 – 1)*100 = 2.35*100 = +235

To convert a decimal of less than 2.00:

moneyline = (-100) / (decimal -1)

Examples:

1.9091 : (-100)/(1.9091 – 1) = (-100)/(0.9091) = -109.99 = -110
1.6579 : (-100)/(1.6579 – 1) = (-100)/(0.6579) = -151.98 = -152

Fractional to American

Over 1/1: Convert Fraction to Decimal and multiply by 100.

Moneyline = (fraction value)*100

Examples:

7/4: (7/4) * 100 = (1.40) * 100 = +140
6/5: (6/5) * 100 = (1.20) * 100 = +120

Under 1/1: divide -100 by the Fraction as a Decimal.

Moneyline = -100/(fraction value)

Examples:

1/4: -100/(1/4) = -100/.25 = -400
1/10: -100/(1/10) = -100/.1 = -1000

Fractional to Decimal

Convert the fraction to a decimal and add one.

Examples:

3/4: (3/4) + 1 = (.75) + 1 = 1.75
6/5: (6/5) + 1 = (1.20) + 1 = 2.20

American to Decimal

Positive Odds (“+”): Divide the moneyline by 100 and add 1.

decimal = (moneyline/100) +1

Examples:

+100: (100/100) + 1 = 1 + 1 = 2.00
+235: (235/100) + 1 = 2.35 + 1 = 3.35

Negative Odds (“-“): Divide 100 by the moneyline, then add this value to 1.00.

decimal = (100/moneyline) + 1

Examples:

-110: (100/110) +1 = 1 + 0.9091 = 1.9091
-152: (100/152) +1 = 1 + 0.6579 = 1.6579

American to Fractional

Positive Odds (“+”): Divide the moneyline by 100 and reduce to simplest form

(moneyline/100) -> simplest form

Examples:

+120: (120/100) = 6/5
+250: (250/100) = 5/2

Negative Odds (“-“): Divide 100 by the moneyline and reduce to simplest form

(100/moneyline) -> simplest form

Examples:

-120: (100/120) = 5/6
-300: (100/300) = 1/3

Odds Converter

Skip the math and easily convert odds between Fractional, Decimal and American format:

Decimal To Fractional Odds Formula

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Decimal Odds Calculator

Want to learn more? Read this full article on betting odds conversion.