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Betting Sites » Bet Calculator » Odds Converter

Odds Converter

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Odds Converter

Enter Your Odds (Converts Automatically)
Fraction
/
Decimal
American
Implied Probability (%)

Use our odds converter tool to convert fractional odds to decimals and vice versa. You can also see find the equivalent American odds values, and see what fractional and decimal odds convert too in percentage terms. Using the odds converter is very straightforward in that the American, decimal and fraction odds will automatically update once you input one value, but we’ll also explain how to calculate odds conversions without the tool below.

How to Convert Fraction Odds to Decimals

You can convert fractional odds into decimal odds by dividing the first number (the numerator), by the second number (the denominator), and adding 1. Example: To convert fractional odds of 6/5, start by dividing 6 by 5 to get 1.20. Then add 1, and you’ll get the decimal odds equivalent of 2.20.

How to Convert Decimal Odds to Fractional

Converting decimal odds into the equivalent fraction odds can be trickier than the reverse process, so using our betting odds calculator is definitely your best bet here.

If you’re starting with decimal odds of 5.0, you just need to subtract one and you’ve got the fractional odds of 4/1.

Some examples can be harder to work out in your head though. Subtracting one from decimal odds of 3.5 gives fraction odds of 2.5/1. However betting sites never use fraction odds which contain a decimal point, so the top and bottom number are both multiplied by two to get the more commonly seen decimal odds of 5/2.

How to Convert American Odds to Decimal

To convert American odds into decimals might seem like a difficult concept to grasp, but you’ll be pleased to hear that we found the process relatively simple. Below, you’ll find a couple of examples for converting American odds into decimals.

How to Convert Positive American Odds to Decimal

For positive American odds, you’ll have to divide the money line by 100, before adding 1. Below, you’ll see an example of this process.

  • American Odds of +250.
  • 250/100 = 2.50
  • 2.50 + 1.00 = 3.50

How to Convert Negative American Odds To Decimal

For negative American odds, you should disregard the negative symbol in front of the odds for calculating it into a decimal. You’ll need to divide 100 by the American odds, before adding 1.

  • American Odds of -130.
  • 100/130 = 0.76
  • 0.76 + 1.00 = 1.76

What are the main types of betting odds?

There are three different types of betting odds which you can use, and you can typically choose which type of betting odds to use as they should be available on all betting sites. The three different formats have no effect on the odds, they are just alternate ways of using them. Here are the three odds with examples of what they look like on bet365.

Decimal (European) Odds: These odds show you how much you could win for every £1/$1 bet.

Image: December 2024

Fractional (British) Odds: These odds show the ratio of the amount of profit you could win if your bet comes through.

Image: December 2024

Moneyline (American) Odds: These odds are slightly different as they could have a + or a – symbol beside them. If there is a negative sign in front of the number, it shows you how much you need to bet to win £100. If they have a + sign then it shows the amount you win if you bet £100.

Image: December 2024

How to calculate Implied Probability from Fractional Odds

Using our betting odds converter to calculate the implied probability is undoubtedly the quickest and easiest method to use, but you can also help to know the manual conversion process. Divide the second number by the total of the first number and second number. Equation:  Denominator / (numerator+ denominator ) * 100 = implied probability Example: 4/1 implied probability can be calculated as 1 / (4+1) * 100 = 20%

How to calculate Implied Probability from Decimal Odds

Again, using our betting odds calculator for your odds conversion from decimal odds to implied probability is the simplest solution, but the manual process is as follows. Divide 1 by the decimal, and multiply it by 100%. Equation:  (1/ decimal odds) * 100 = implied probability Example: 1 /4.00 * 100 = 25%

Find other bet calculators plus hundreds of pounds in attractive betting offers, including the bet365 bonus code.

Odds Conversion Table

As an alternative to using our betting odds converter, you can also check out the most common fractional odds below, alongside the decimal odds, American odds and the implied probabilities of each set of odds.

Using the Fulham vs West Ham example, you can scan the table to see Fulham are 11/8 to win the match, which can also be written as 2.37 in decimal odds or +137 in American odds, with an implied probability of around 42% of claiming victory. This compares to West Ham who are priced at 2/1 in fractions, 3.0 in decimals and +200 using American odds, with an implied probability of 33%.

FractionDecimalAmericanProbability
1/1001.01-1000099%
1/101.1-100090.9%
1/61.17-60085.7%
1/51.2-50083.3%
1/41.25-40080%
1/31.33-30075%
2/51.4-25071.4%
4/91.44-22569.2%
1/21.5-20066.7%
8/151.53-18865.2%
4/71.57-17563.6%
8/131.62-16261.9%
4/61.67-15060%
8/111.73-13757.9%
4/51.8-12555.6%
5/61.83-12054.5%
10/111.91-11052.4%
Evens2.0+10050%
11/102.1+11047.6%
6/52.2+12045.5%
5/42.25+12544.4%
11/82.37+13742.1%
6/42.5+15040%
13/82.63+16338.1%
7/42.75+17536.4%
15/82.88+18834.8%
2/13.0+20033.3%
9/43.25+22530.8%
5/23.5+25028.6%
11/43.75+27526.7%
3/14.0+30025%
10/34.33+33323.1%
7/24.5+35022.2%
4/15.0+40020%
9/25.5+45018.2%
5/16.0+50016.7%
11/26.5+55015.4%
6/17.0+60014.3%
13/27.5+65013.3%
7/18.0+70012.5%
15/28.5+75011.8%
8/19.0+80011.1%
9/110.0+90010%
10/111.0+10009.1%
12/113.0+12007.7%
14/115.0+14006.7%
16/117.0+16005.9%
18/119.0+18005.3%
20/121.0+20004.8%
25/126.0+25003.8%
33/134.0+33002.9%
50/151.0+50002%
100/1101.0+100001%

Odds Converter FAQs

Simply enter the type of odds your dealing with (fractional, decimal, American or implied probability) into our betting odds converter. The other ways of describing those odds will then be accurately calculated and instantly displayed. For example, entering fractional odds of 4/1 will show you the decimal equivalent is 5, the American equivalent is +400, and the implied probability is 20%

Using the odds converter helps you to understand any odds you find by converting them to the odds type you are most familiar with. For example, if you use a specific betting site and realise they use fractional odds, you can convert those odds to decimal odds that you may be more familiar with. Most of the best betting sites will also allow you to toggle between different odds types in their settings.

You can use our betting odds converter for any participant, market or sport you’d like.

Fraction or fractional odds tell you the ratio of profit you’ll win compared to the stake of your bet. For example, fractional odds of 6/1 tells you that you can win 6 times the size of the bet you place.

You should use the type of betting odds you feel most comfortable with. Traditionally, UK betting sites use fractional odds, but European sites, and indeed many newer sites, often default to decimal odds instead.

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