Betting Odds – A Complete Guide

betting odds guide

For some, starting their matched betting journey is a relatively seamless experience. There may be a few new methods and strategies to learn but the idea of placing bets online isn’t daunting. However, for many people it can be a little more difficult; especially if they have never placed a bet before. One obstacle you must overcome if you want to make a success out of matched betting is understanding betting odds. Hopefully, this guide will help you get to grips with odds and the differences between odds formats.

First, let’s take a look at what betting odds are.

Odds, when betting, show us how much our returns will be should our bet win based on our stake. Unfortunately, odds come in various formats with UK bettors predominantly using either decimal or fractional odds which we will look at below.

Odds can also represent the probability of an event occurring. For example, if you roll a dice, there are 6 possible outcomes. Each outcome has the same probability with a 16.7% chance. Of course, bookies don’t show the probability percentage of a bet. Instead they offer odds which reflect this probability. The odds on a doll of a dice would be 5/1 in fractional format or 6.0 in decimal.

If you wish to work out the probability based on any given odds, you can do this using a simple formula.

Let’s say that a bet had odds of 10/1. What is the probability of it occurring as a percentage?

Probability = B / (A+B)

Where A is first number in the odds (10) and B is the second number (1).

Probability = 1 / (10-1) = 0.11

This means that odds of 10/1 mean that there is a 11% chance of it occurring.

Fractional Odds

Factional odds are commonly used by punters in the UK and also by betting sites on advertisements and promotions. 

If you place a bet with a stake to the value of the number on the right, your profit will be the number on the left.

For example:

  • Odds of 2/1: If you bet £1, you will profit £2 (£3 total return)
  • Odds of 10/1: If you bet £1, you will profit £10 (£11 total return)
  • Odds of 7/2: If you bet £2, you will profit £7 (£9 total return)
  • Odds of 9/4: If you bet £4, you will profit £9 (£13 total return)

As you can see, it’s simple to calculate your profit if your stake is the number on the right. However, odds in this format can sometimes a pain when when not.

For example, if you were to place a £3 bet at odds of 9/4, it becomes slightly more difficult to calculate your returns.

Decimal Odds

When matched betting, it is always recommended that you use decimal odds as this is what are used on betting exchanges and they’re also a lot easier to calculate your returns regardless of the stake used.

With decimal odds, you simply need to multiply your stake by the odds and you have your potential returns.

For example:

  • Odds of 3.0: If you bet £1, your returns would be £3 (£2 profit)
  • Odds of 7.6: If you bet £1, your returns would be £7.60 (£6.60 profit)
  • Odds of 10.0: If you bet £2.50, your returns would be £25 (£22.50 profit)

Converting Fractional to Decimal Odds

There may be a time when you need to convert fractional odds to decimal. To do this is easy and there’s a simple formula for it.

Simply divide the fraction and add 1 and you have the decimal odds.

For example:

  • 10/1 = 11.0
  • 3/1 = 4.0
  • 7/2 = 4.5

There are many tools online which can help you convert odds into different formats but it’s always good to know how to manually do it. Some tools however are extremely handy. For example, when playing poker, a poker odds calculator can help you determine the probability of winning a hand which can help you decide on the right call to make. When matched betting, we always recommend that you use a calculator as it can be easy to make a mistake when backing and laying bets which can cost you money.