Comparing Sports Odds Explained

Comparing Sports Odds Explained

Sports betting is big business these days, thanks to the Supreme Court decision of May 2018, which paved the way for the states to legalize their own sports betting markets.


In the years since that landmark decision, sports betting fans across the US have enjoyed a growing sector, which has given them the ability to bet on a wide range of sports with the likes of offering a growing variety of sports betting markets.


For those new to sports betting, however, there are some aspects that require some explanation. One area requiring some explanation is the concept of odds and the way they are used.


All About Odds


Odds are an essential part of the betting experience. It is the odds on a market that you reckon with when you are deciding whether to make a wager and for how much. But what exactly are odds?


Odds essentially perform two functions. First, they tell you about your potential return on a bet. The longer the odds, the bigger the potential reward. But there’s a trade-off for that bigger reward. That’s because odds also represent probability. The bigger the odds and the pay-off, the smaller the probability of that selection winning. Weighing up these two factors: price and probability, is central to sports betting.


When a market is launched, the sportsbook will quote odds on all of the potential winners of that event, which roughly represent their respective winning chances, according to the sportsbook’s odds compilers, with, of course, a little extra margin added on top. That extra margin is the sportsbook’s profit, and it explains why the probability value of a set of odds in any market will always be greater than 1.0.


Moneyline Odds


US bettors will almost always deal with the Moneyline odds format. A typical set of Moneyline odds for the winners’ market on an NFL game may look like this:



In this game, the Dallas Cowboys are the favourites to win. As there is a minus figure beside their price, this means that the odds equate to the amount of money you would need to wager to win $100. As you can see, in this case, that would be $180. For the Giants, the odds refer to your return on a successful $100 bet, so a winning $100 bet on the Giants would pay out a profit of $125.


Other Odds


Occasionally, however, US sports bettors may come across other odds formats and it helps to be aware of what they are and how they work.


Fractional Odds


These odds aren’t very widely used outside of the UK and Ireland, but as that part of the world is a very strong betting market, it is worth knowing how they operate.


Typical fractional odds are expressed as two numbers, and to work out the potential profit on a bet, you merely divide the first number by the second. For example, 2/1 means you win twice your stake, while 1/2 means your profit is half your stake and so on.

Decimal Odds


This odds format is the most common outside of the US and the UK and has the advantage over fractional odds of offering greater precision. The key thing to remember with decimal odds is that the value of the stake is included in the odds. So, odds of 2/1 would be translated to 3.0 in decimal odds. If you want to work out what multiplier of your stake would be on a winning bet, simply remove 1 from the decimal odds figure.


Comparing Odds


Knowing how to read and compare different formats of odds is useful, but even more important is being able to compare odds at different sportsbooks. There are numerous odds comparison services online and it is always useful to employ one of these to find the very best odds.


Another way of comparing odds is to change them into probability figures. This enables you to compare the sportsbook’s opinion with your own and decide if you think they are wrong. This is the essence of success in sports betting. To do this, you will need to use two different calculations:


If the Moneyline odds are a minus figure: Remove the minus sign, then: Odds/(Odds +100)

If the Moneyline odds are a plus figure: 100/(Odds + 100)


So, converting the odds on the NFL game we quoted earlier would give us these probabilities:


  • Dallas Cowboys 0.64
  • New York Giants 0.44


As you can see, these probabilities add up to 1.08, and the 0.08 represents the sportsbooks margin. Making a profit despite competing with that margin is tough but getting to grips with odds and how they work is one of the first steps on the challenging road to success in sports betting.