Omni Calculator logo

How much are you going to win with that bet — if everything goes according to plan — won't be a mystery with our decimal odds calculator. Insert the chances, and let us do the math.

Keep reading our short article to learn everything you need to know:

  • What are odds;
  • How to calculate the decimal odds of a bet;
  • How to use decimal odds to calculate a bet's return.

Omni Calculator doesn't support gambling or betting: we believe in numbers and science, which is this tool's scope. Bet responsibly: gambling causes addiction.

Odd: the mathematics of a bet. What are decimal odds

When you are betting, you assign a value to the likelihood of the outcome of an event. It sounds complicated, doesn't it?

Let's try to put it in simple words. Take an event with a defined set of outcomes. It can be any event: a soccer game, a horse race, the possibility of finding good weather on your hike, or being hit by a pot of petunias falling from the sky.

A pot of petunias
Oh no, not again. The odds of a pot of petunias materializing in the middle of the sky are abysmally small.

You can assign chances to those outcomes. A chance represents the likelihood of one of those outcomes: 5 chances of winning on a total of 6 games, one chance in a million to win the lottery.

You can calculate those chances or let someone figure them out for you. Chances can come in various aspects, but usually, we express them as a pair of numbers — at least when the outcome is dual:

  • The chances of success; and
  • The chances against success.

🙋 Omni has many tools that can help you calculate the odds and probability of many types of events: try our dice probability calculator, our lottery calculator, or our coin toss streak calculator.

That's all it matters for you.

Now, you will bet on one of those outcomes: the one you choose will represent your chances of success. It depends on you: are you willing to take a risk for a high return, or do you prefer to play safe?

You can easily calculate the probability of losing or winning the bet:

PW=CsCs+CasPL=CasCs+Cas\begin{align*} P_{\text{W}} &= \frac{C_{\text{s}}}{C_{\text{s}}+C_{\text{as}}}\\ \\ P_{\text{L}} & = \frac{C_{\text{as}}}{C_{\text{s}}+C_{\text{as}}} \end{align*}


  • PWP_{\text{W}} - Probability of winning;
  • PLP_{\text{L}} - Probability of losing;
  • CsC_{\text{s}} - Chances for success; and
  • CasC_{\text{as}} - Chances against success.

You can express these results either in percentage or as a decimal number.

Now it's time to calculate your odds. The decimal odds are an intuitive way to calculate your return in the case of a winning bet. Follow us: we will teach you how to calculate the decimal odds of your bet.

How do I calculate the decimal odds of a bet? Expressing probability with numbers

To calculate the decimal odds of a bet, you only need to know the winning and losing chances.

The formula for the decimal odds is:

odds=Cas+CsCs\text{odds} = \frac{C_{\text{as}}+C_{\text{s}}}{C_{\text{s}}}

The higher the number, the higher the probability of you losing the bet.

🙋 Decimal odds are widely used in continental Europe in the betting environment. Other regions use different systems: in the UK, you will find fractional odds, while in the US, the most common way to display odds is called... "American odds".

What do you do with the result of the calculations for the decimal odds? You can calculate the return, for example!

Using decimal odds to calculate the return: how much will you profit?

Decimal odds quickly tell you how much would be your total return in case of a winning bet. This way, you will find how much money would return in your pocket, not the net profit. You use decimal odds to calculate the return of your bet by multiplying the stakes of your bet by the decimal odds' value.

r=soddsr = s\cdot \text{odds}


  • rr - The gross return;
  • ss - The stake of your bet; and
  • odds\text{odds} - The decimal odds.

To calculate the net return, subtract rr and ss:

rnet=rsr_{\text{net}} = r-s

What are the odds? Other useful calculators

As you know, there are many ways to write the odds of the same bet. Try our odds calculator for an overview of all of them or our fractional odds.

An example of how to calculate the decimal odds and the return

Say that you are betting against the sky that you will get hit by a meteor. Scientist estimated this event to have chances 11 in 250,000250,000. This is an admittedly silly bet, so don't raise your stakes: $10\text{\textdollar}10 will be enough.

What are the decimal odds of your bet?

odds=250, ⁣000+11=250, ⁣0011\text{odds} = \frac{250,\!000+1}{1} = \frac{250,\!001}{1}

That was pretty straightforward. The return of your bet in case the rock hits you would be 2,500,0102,500,010. We hope you can enjoy them.


What are the type of odds?

You can express odds in three ways:

  1. American odds: odds normalized over a stake of $100;
  2. Fractional odds: odds against the losing chances (used in the UK); and
  3. Decimal odds: odds against all chances (used in continental Europe).

What's the difference between decimal and fractional odds?

Decimal odds and fractional odds are different ways to express the same concept, a way to calculate the return of a winning bet.

  • We express a decimal odd with a single number, e.g., 13.7. Multiplying the decimal odds by the stake gives the gross return.
  • We express the fractional stakes as an integer fraction. Multiplying this fraction by the stake gives us the net return.

How do I calculate the decimal odds of a bet?

To calculate the decimal odds of a bet, you must know:

  • Cs - The chances of success; and
  • Cas -The chances against success.

To find the decimal odds, apply the formula:

odds = (Cs+Cas)/Cs

What is my return if I bet $100 with decimal odds 13.5?

Your return is $1,350. The decimal odds 13.5 correspond — roughly — to the chances of rolling a combination of 6 dice summing to 18.
The probability of losing is 92.5% while winning is 7.5%. The chances are about 8 to 100.

Calculate the decimal odds and multiply them by the stake to find your return r:

r = s × (Cs+Cas)/Cs = 100 × (100+8)/8 = $1,350


  • Cs - chances of success; and
  • Cas - chances against success.
Davide Borchia
Chances for success
Chances against success
Probability of winning
Probability of losing
Fractional odds:
Decimal odds
Total returned
Potential net profit
Disclaimer: Omni Calculator does not recommend any form of betting.
Check out 33 similar probability theory and odds calculators 🎲
AccuracyBayes theoremBertrand's box paradox… 30 more
People also viewed…

Humans vs vampires

Vampire apocalypse calculator shows what would happen if vampires were among us using the predator - prey model.

Minimum and maximum

The minimum and maximum calculator will quickly give you the smallest and largest values in your dataset of up to fifty entries.

Plant spacing

Optimize your garden layout with our garden spacing calculator. Perfect for precise plant spacing. Plan your dream garden effortlessly now!

Z score

The z-score calculator can help you determine the standard score for a data point.
Copyright by Omni Calculator sp. z o.o.
Privacy, Cookies & Terms of Service