On this page, we explain about odds in some detail. We define exactly what they are and the role they play. We also look at the three different formats in which they can be expressed, and explain why odds on the same outcome can vary with different bookmakers.

Second, odds also reflect the likelihood of any particular outcome happening. The more likely an outcome, the lower they will be. This makes perfect sense, as you would expect to win less when betting on an outcome that's likely than when betting on an outcome that is unlikely.

Imagine a tennis match where the player ranked number one in the world is pitted against the player ranked 137th. It stands to reason that the best player in the world is going to be considered more likely to win than his opponent. Therefore, a wager on his winning would have very low odds; a wager on his opponent winning would have much higher odds.This is a somewhat simplified explanation, but it gives a general idea of the role of odds in

+ Moneyline/American Odds

+ Decimal Odds

+ Fractional Odds

Chances are, at some point, you'll encounter each of these formats. For this reason, it pays to be familiar with each one. They all work in essentially the same way--basically just different ways of expressing the actual odds for any particular wager.

If you saw odds of +150, you would know that a $100 bet could return $150 in winnings, plus the initial stake of $100. If you saw -150, you would know you need to stake $150 to return $100 in winnings, plus the initial stake of $150. An even money wager (where you stand to win an amount equal to your stake) is expressed as +100.

The number shows how much the total payout will be, including the original stake per unit staked. For example, a winning bet at 1.5 would return a total of $1.50 for every $1 staked. A winning bet at 2.25 would return a total of $2.25 for every $1 staked. An even money bet is expressed as 2.00.

As the name suggests, these odds are displayed as a fraction. A simple example is 3/1, which is said as "three to one". 5/1 is said as "five to one", and so on. With 3/1, you can win three units for every one unit staked, and with 5/1 you can win five units for every one unit staked. 1/1 is even money, so you can win one unit for every unit staked. As you can see, this is quite straightforward so far.

Things get slightly more complicated, because this format also includes examples such as 6/4, 11/10, and 5/2. The math involved is thus not always so simple. With 6/4, you can win six units for every four units staked, which is equal to 1.5 units per unit staked. With 11/10, you can win eleven units for every ten units staked, or 1.1 units per unit staked.

Whenever the first number is larger than the second, this is said to be "odds against." These are basically the equivalent of positive moneyline odds in that the potential profit is greater than the amount staked. Things get even more complicated as there are also "odds on" odds. These are the equivalent of negative moneyline odds in that the potential profit is less than the amount staked.

An example of odds on is 1/4 is said as "four to one on". 4/7 is "seven to four on", and so on. With 1/4, you can win one unit for every four units staked, and with 4/7 you can win four units for every seven units staked.