Decimal Odds

Decimal Odds

What are Decimal Odds 

Decimal odds, also referred to as European odds, are fast becoming the dominate odds format across the internet, but with British Bookmakers being the major player in this market fractional odds are still very prevalent, this is more for the older punter though. The modern education system as it stand makes the use of decimals odds far easier for the younger punters as this format is one they are most comfortable with. Also, without question, decimal odds are by far the easiest to use when needing to calculate accumulators and combination multiples.

In general most betting firms will have an allowed odds list for decimals; these will normally be decimals of their user friendly fractional equivalent, making it easy for their customers to switch between the different odds formats. A lot of the time the odds will just be displayed as a whole number and not have a decimal point, such as 5 and not 5.00. When the odds do have decimals the vast majority of betting companies keep these to just two decimal places, although it is becoming common practise to change to three decimal places once the odds go below 1.01

Decimal odds customarily have a standard increment or decrement within certain odds ranges, this is more obvious went betting with the betting exchanges as you are the one that offers or takes the odds. But bookmakers also follow this custom as a rule, with the elimination of certain odds that don’t fit their allowed odds chart. The increments can be observed it the below table, this is just a rough guide and some bookmakers and betting exchanges may deviate from it slightly.

Odds RangeOdds increment
1.001 – 1.010.001
1.01 – 20.01
2 – 30.02
3 – 40.05
4 – 60.1
6 – 100.2
10 – 200.5
20 – 301
30 – 502 or 5
50 – 1005

Converting Decimal odds to Fractions 

For converting decimal odds to fractions there isn’t an exact formula that fits every decimal. This is due to the number of decimal points, how many different steps are involved to simplify the fraction and weather the decimal is recurring or not (recurring decimals are ones in which the number after the decimal point repeats forever. Like 2.2222…..). There is, however, a general method in which to follow.

Step 1: Subtract 1 from the decimal.

Step 2: Write the resulting decimal as decimal divided up 1 (decimal / 1)

Step 3: Now multiple both top and bottom of the fraction by a multiple of 10 for each number after the decimal point. For sports betting odds this very rarely goes beyond 2 places, so will therefore be either 10 or 100.

Step 4: Simplify the fraction. If you are more familiar with fractional odds than you are decimals you will know that bookies don’t always use the most simplified fraction. For example, 100/30 is a common fraction as is 6/4. Both of these could be reduced even more, to 10/3 and 3/2 respectively.

Something to keep in mind also is you can’t do this method if it is a recurring fraction. This is because you will be multiplying by an infinite multiple of 10. To solve this it is best to look at a quick example, and using a very strange bit of maths knowledge, that 0.999 = 1. Nobody believes this at first so let’s have a look how.

x = 0.999…

If we multiple both sides by 10 we get

10x = 9.999…

Now subtract x from each side

10x – x = 9.999… – x

But as we know x = 0.999… we can sub this into the right hand side of the equation

9x = 9.999… – 0.999…

9x = 9


x = 1

How does this little maths trick help us I hear you ask. Well let’s say the decimal is 0.3 recurring.

Using the Step 1 we get 0.333/1

Now multiple top and bottom by 3 we get 0.999/3

And as we now know 0.999 = 1 we have a nice easy fraction of 1/3

Converting Decimal odds to American odds

Converting decimal odds to American odds, or moneyline odds as it’s often called, is very simple. This type of conversion can easily be done in your head, without the need for a calculator. In fact anyone new to betting should consider decimals as the best choice of odds to get familiar with as it is the easiest format of odds to work with, weather is it working out payments, calculating stakes or as in this case, converting odds to other formats.

The only difficult part for converting decimal odds to American odds is remembering there are two separate rules. One rule for odds-on shots and one for odds greater or equal to even money.

For odds ≥ Evens, American odds = 100 x (Decimal odds – 1)
For odds < Evens, American odds = -100 ÷ (Decimal odds – 1) When American odds are positive it represents the amount that is won from a hundred units staked and when negative it represents the amount that needs to be bet to win a hundred unit stakes. For example, +300 means if you bet 100 you win 300 and -300 means if you bet 300 you win 100.

Converting Decimal odds to Hong Kong odds

Hong Kong odds are by far the easiest odds format to convert a decimal to. Hong Kong odds are expressed as the profit made from a unit stake, somewhat like fractional odds are but in a decimal format. As decimal odds are the profit made from a unit stake plus your original stake the calculation to work out Hong Kong odds is simply subtracting that stake. Hong Kong odds = Decimal odds – 1 Hong Kong odds, along with Decimal odds are a very good format to work with. The profit for any bet is simple the stake multiple the odds. So Hong Knog odds of 3.5 would give you a profit of £3.50 for every £1 bet.

Converting Decimal odds to Indonesian odds

Indonesian odds, very often mistaken for Hong Kong odds, because they are exactly the same when above evens. This odds format is actually the same as American odds except they are for one unit stake opposed to a hundred units staked in American odds So just as with American odds there are two different formulas, one for odds-on prices and one for above evens. For odds ≥ Evens, Indonesian odds = Decimal odds – 1 For odds < Evens, Indonesian odds = -1÷ (Decimal odds – 1) The first one giving you what you can win from a single unit staked, the other giving you what you need to bet in order to win a unit.

Converting Decimal odds to Malay odds

Malay odds are always between -1 and 1. Like several other odds formats they have a different method of conversion from decimal based on whether the odds are greater or less than even money. For odds ≥ Evens, Malay odds = Decimal odds – 1 For odds < Evens, Malay odds = -1 / (Decimal odds – 1)

Converting Decimal odds to Implied probability

Implied probability is probably the easy way for someone to visualise their chances of a winning bet. This is because although implied probability is a number between 0 and 1 it is very often represented as a percentage. Saying to a punter you have a 20% chance of success normally means more to them than saying decimal odds of 5, fractional odds 4/1 or American odds of +400. But then I guess the bookmakers don’t really want you to understand your chances, but want you to focus on what you could win. Implied probability = 1 / Decimal odds If you want this as a percentage simple multiply it by a hundred

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