Betting Odds Explained

Anyone harbouring hopes of making a profit from sports betting must first get to grips with how the different odds work. Betting odds are effectively a prediction of how likely it is that a particular event will happen and allow you to work out how much you will win if your wager is successful.

At Bettingtop10 we are eager to help punters beat the bookmakers, so read our guide to understanding sports betting odds.

How to Read Betting Odds?

Odds are generally presented in one of three different formats – fractional, decimal or Moneyline – all of which represent the percentage probability of a particular outcome.
In simple terms, sports betting odds are set by bookies as a way of telling punters who they think is most likely to win an event.

For instance, if you bet on horse racing you may see odds of 1/2 – this means that the horse is strongly fancied and predicted to have a 66.7% chance of winning the race.
By contrast, a horse priced at 9/1 would be thought to be less likely to finish first as the odds imply a winning probability of just 10%.

Your returns on a £20 bet on the 1/2 horse would be £30 if it won (£10 profit + £20 stake), while the same stake on a 9/1 winner would give you £200 (£180 profit + £20 stake).


American Sports Betting Odds (Moneyline)

Moneylines are often used by bookies to highlight the odds in major North American sports such as basketball, baseball or ice hockey.
Mathematical symbols are used alongside numbers to display the odds, with the minus sign (-) determining the favourite and the plus sign (+) the underdog.

An example of how a moneyline works in the NBA is as follows:

  • Toronto Raptors: -180 – A £180 bet would return £280 if the Raptors win (£180 stake + £100 profit)

  • Boston Celtics: +200 – A £100 wager would pay £300 if the Celtics were successful (£100 stake + £200 profit)

How Fractional Odds Work?

Fractional odds are a staple part of sports betting in the UK, with most online bookies across the industry using them to display their odds.
As the name implies, the odds for a particular event are displayed as fractions such as 4/6, 3/1, 11/2, 10/1 and so on. The number on the right is the stake needed to win the number on the left.

Fractional odds work as follows:

  • Bet £60 on Liverpool to win the Premier League at odds of 4/6. If they are successful you receive £100 (£60 stake & £40 profit).

  • Wager £20 on Shishkin to win the Arkle chase at the Cheltenham Festival at odds of 11/2. If the horse wins your returns would be £130 (£20 stake + £110 profit).

How Decimal Odds Work?

The growth of betting exchanges has led to an increase in the number of sites who use decimal odds.

These odds are perhaps slightly easier than either moneyline or fractional to fathom, particularly amongst younger punters.

Decimal odds are calculated as follows:

  • Bet £10 on Tiger Roll to win the Grand National at odds of 6.00. If the horse wins you receive £60 (£10 x 6.00 = £60).
  • Place a £20 wager on Manchester United to win the Champions League at odds of 10.00. If they lift the trophy your returns would be £200 (£20 x 10.00 = £200).

FAQs About Sports Betting Odds

Online bookies employ odds compilers to set the odds. These people are generally experts within specific sports.

Bookies set odds in advance based on the probability of certain outcomes occurring. Injuries, loss of form and changes in playing conditions are amongst a plethora of factors that can cause odds to fluctuate.

Some bookies excel in certain sports, so opening an account with a few different ones will help you obtain the best odds.

Most prices are set in stone, but it is feasible to request better odds via betting exchanges.

Sports betting sites regularly offer ante-post odds on big events months in advance. These are often a great way to obtain extra value.

Sports Betting Odds – Summary

Fractional, decimal and moneyline odds are all displayed differently, but they each perform the same function of representing the probability of a particular outcome and telling you how much you can win.

This guide has given you the basic knowledge you need to understand the different formats and how they work in the real world.

Good luck with your wagers!

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