Your All-Important Guide to Odds Conversion in Sports Betting: What You Need to Know

Sports betting is becoming more and more popular, simply because (aside from getting the opportunity to make a lot of money) there is a lot of excitement and fun around the various games that are on offer.

However, it’s not always easy to make sense of the mathematics. Different platforms may use different ways of calculating, and it’s often confusing on how exactly the various odds and probabilities are calculated. Want to clear away the puzzlement? Here’s your all-important guide to odds conversion in sports betting: what you need to know.

Knowing what you’re talking about

It’s often hard to know what the bookie is talking about when they’re throwing out numbers – in fact, they often have different ways of explaining the same thing. First things first: understand the various forms the bookie can relay information, and see which applies to you. It’s the format that will help you understand your chances. A decimal odds-format of 4.00 means 25% probability or a 1/3 odds. Check the format first.
It’s all about math

It really doesn’t require a lot of math – but you need to know how to add, how to divide, and which to do at what time. Here’s a quick guide.

Converting odds to probability

Once you understand which format you are in, it’s easy to see how you can convert it to another format (to whichever you feel most comfortable with). Check the following:

  • Decimal odds. To calculate your probability, simply divide 100% by the decimal number. For example, decimal odds of 6 become 16.67%.
  • Fractional odds. Add the two numbers of the fraction together and divide 100% by that number. Next, multiply that by your odds of winning. For example, if your odds are 1/3, then divide 100% by 4 (1+3) and multiply that by 1 – so 25%.
  • Moneyline odds. Take the true value of your moneyline odds, add 100, and proceed like fractional odds. For example, if your odds are -120, then add 100 (120+100), so you arrive at a probability of 54.5% (120/220).

Converting probabilities to odds

When it comes to converting probabilities to odds, all you have to do is reverse the procedures outlined above. Hence, a 20% probability becomes a 5.00 decimal odds, ¼ fractional odds, and +/-400 moneyline odds.

There are many tools online, such as a useful odds conversion calculator, which you can use to convert odds into probabilities, and vice versa. Both odds and probability calculations are supposed to add up to a certain number. Learning to read the numbers is easy – but very important. You need to know what you are in for, after all.




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