The Science of Football Betting: Understanding the Odds

Football betting used to be a popular way to up the ante during a derby. Today, it’s a whole other beast. There are millions upon millions of casuals, many of which have only watched a handful of football games in their lives, who make weekly accumulators and indulge in sportsbook offers. And, as seen on Match Center, there are a lot of offers.

But, those who love football and those who see it purely as a betting opportunity share one thing in common: they will see no success if they do not understand betting in and of itself. This means knowing how odds work, bet builders, features, types of markets, bankroll strategies, and many other things. Today, we will focus on odds.

UK, US, and EU odds

Unfortunately, there is no standardised format for odds. In the UK, odds are represented as a fraction. So, 10/1 means that a £10 bet will result in £100 winnings (plus the £10 stake back). The same odds in a decimal format, commonly used by the EU, is 11 (i.e. betting €10 returns €100 + €10). And, the Moneyline format, popular in the US, is 1000.

The only one here that doesn’t seem intuitive right away, much like Fahrenheit, ounces, and inches, is Moneyline. The number can be negative, like -150, which means that you would need to bet $150 to win $100. A positive number, such as +200, means that you would win $200 for every $100 bet. 

Implied probability

Odds reflect the implied probability of an event happening. For example, 1/1 odds (known as evens), means that you double your money if you win, like choosing red on roulette. The implied probability here is that the bookmakers believe it has a 50% chance of happening. 7/1, therefore, has a 12.5% implied probability.

Only, that would be the implied probability in the perfect world where expected value is fair. But, sportsbooks are here to make money, so they claim a house edge. In the example of a casino, the green 0 means that the actual odds of the ball landing on red is slightly under 50/50, yet these are the odds you get. This means you don’t have perfect value, and if you played forever, you would eventually lose. Football odds work in the same way, the odds almost reflect the probability of an outcome, but we must factor in two things: house edge and imperfect prediction.

How bookmakers determine odds

A lot of bookmakers share similar software, SaaS, or methods in how they determine the odds. Usually, it’s a very complex algorithm that calculates statistics, news, expert analysis, and even AI. However, odds can often be swayed by supply/demand too, so that if a certain underdog is receive a large number of bets, the odds may get shorter (i.e. from 5/1 to 4/1). 

This is where you can make some astute bets surrounding timing. Often, horses and other sports opening at certain odds then change over time. If you can bet on one early on and lay at other bookies later, it’s possible to gain arbitrage possibilities (i.e. no-lose situations).