Decimal odds definition

Decimal odds are the odds favoured by bookmakers in continental Europe, Canada, Australia and New Zealand. They provide odds in decimal form.

Decimal odds are relatively straight forward to understand, with the favourite and underdog easy to spot and the total payout relatively simple to calculate.

Decimal odds represent the total payout for every £1 placed on the bet, meaning your initial stake is also included.

For example, if odds of 1.97 were quoted, a £1 bet would see a total payout of £1.97.

How to read decimal odds

Favourites have decimal odds of under 2.00, meaning the bookmaker considers this outcome more likely to happen than not.

Underdogs have decimal odds of over 2.00, meaning the bookmaker considers this outcome more likely to not happen.

Odds of exactly 2.00 are also referred to as evens, meaning the bookmaker is suggesting that this outcome has a 50/50 chance of happening.

Calculating payout using decimal odds

Calculating payout with decimal odds is relatively straight forward, and is determined using the following formula.

Stake * decimal odds

For example

Barcelona vs Real Madrid - Barcelona to win at odds of 1.85 with a £20 stake

20 * 1.85 = 37

Total payout = £37

Converting decimal odds into fractional odds

There is no formula to convert decimal odds into fractional odds, just a little bit of maths to do instead.

Step 1) Convert decimal odds into fractional form by subtracting 1 from the decimal

Step 2) This number becomes the numerator (the first number), and use the number 1 as the denominator (the second number)

Step 3) Convert the fraction into its simplest form by finding the nearest whole number that the numerator divides into.

Step 4) The number by which you times the numerator by to make it into a whole number becomes the denominator.

For example

Atalanta vs Roma - over 2.5 goals at odds of 3.40

Step 1) 3.40 - 1 = 2.40

Step 2) 2.4/1

Step 3) 2.4 * 5 = 12

Step 4) 5/12

Converting fractional odds into decimal odds

To convert fractional odds into decimal odds, the following formula is used:

(numerator / denominator) + 1

For example

Atletico Madrid vs Real Madrid - both teams to score at odds of 5/6

(5 / 6) + 1 = 1.83

Converting decimal odds into American odds

To convert decimal odds of over 2.00 into American odds, the following formula is used:

(Decimal - 1) * 100

For example

Juventus vs Turin - both teams to score at odds of 3.35

(3.35 - 1) * 100 = +235

To convert decimal odds of under 2.00 into American odds, the following formula is used:

-100 / (decimal - 1)

For example

Roma vs Atalanta - Roma to win at odds of 1.65

-100 / (1.65 - 1) = -154

Converting American odds into decimal odds

In order to convert American odds into decimal odds, the following formulas are used.

For positive odds, the formula for converting American odds into decimal odds is as follows:

Odds / 100 + 1

For example

Atalanta vs Roma - over 2.5 goals at odds of +150

150 / 100 + 1 = 2.50

For negative odds, the formula for converting American odds into decimal odds is:

100 / Odds + 1

For example

Inter Milan vs AC Milan - Inter to win at odds of -250

100 / 250 + 1 = 1.40

Converting decimal odds into implied probability

Implied probability is the conversion of odds into a percentage to show the expected probability of an outcome.

To convert decimal odds into implied probability, the following formula is used:

(1 / decimal odds) * 100 = implied probability

For example

Manchester United vs Chelsea - under 2.5 goals at odds of 1.50

(1 / 1.5) * 100 = 66.7%