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Betting odds are a numerical indicator of the probability of an event happening – and also a way to work out how much can be won by betting on the odds in question.
Traditionally – in the UK – odds were presented as fractions. For example, a horse may be priced at 4/1 to win a race. But now many bookmakers and bettors use the decimal format (in this case the horse would have odds of 5.0). There is also an American version that can be used as well.
Odds are vital in sports betting, as they are the way every single market is listed – indicating the probability of an event occurring. Anyone new to betting should first learn what the odds mean and also what they indicate.
To work out the probability percentage of odds a simple formula can be used:
Probability % = B / (A+B)
With the earlier example of 4/1 the 4 is ‘A’ and the 1 is ‘B’ meaning that:
1 / (4 + 1) = 0.20
This means that a 4/1 price suggests that there is a 20% chance of that horse winning the race. The skill in studying the odds is to find the value and bet accordingly. Obviously longer odds will give bettors more winnings but there is less chance of the prediction coming true.
Leicester City were famously 5,000/1 to win the 2015-16 Premier League – and some lucky bettors made a lot of money thanks to one of the greatest upsets in modern football. But as Leicester started that season so well their odds had already shrunk to 10/1 by Christmas and they were odds-on to win by the middle of March.