Reading odds is a critical skill in sports betting. Whether you’re an amateur, beginner, or professional, you need to be able to read the odds in order to make the best possible decisions. In this article, we’ll explain the concepts of American, Decimal, and Fractional odds, and explain how to calculate American odds.
American Odds
American odds, are popular in the United States and Canada. American odds are expressed as a three-digit number that either starts with a plus sign (+) or minus sign (-). For example, a prop bet on an NFL passing yards might be listed as +200 or -200.
If the odds start with a minus sign, the number indicates how much money you must bet to win $100. In this example, you must bet $200 to win $100.
If the odds start with a plus sign, the number indicates how much money you will win if you bet $100. In this example, you will win $200 if you bet $100.
Decimal Odds
Decimal odds, also known as European odds, are popular in Europe, Australia, Canada, and New Zealand. Decimal odds are expressed as a number, usually to two decimal places. For example, a prop bet on an NBA total might be listed as 1.97.
In decimal odds, the number always indicates how much money you will win, including your original stake. In this example, if you bet $100, you will win $197 (including original stake).
Fractional Odds
Fractional odds, also known as UK odds, are popular in the United Kingdom. Fractional odds are expressed as a ratio. For example, a prop bet on an MLB moneyline might be listed as 5/1.
In fractional odds, the ratio indicates how much money you will win, including your original stake. In this example, if you bet $100, you will win $500 (including original stake).
How to Calculate American Odds
To calculate American odds, you first need to determine whether the odds are positive or negative. If they are positive, then you can calculate the implied probability by dividing 100 by the number.
For example, the implied probability of +200 odds is 100/200 = 0.50 or 50%. This means that the sportsbook believes that the team has a 50% chance of winning.
If the odds are negative, then you can calculate the implied probability by dividing the number by 100 and adding 1.
For example, the implied probability of -200 odds is (-200/100) + 1 = 0.67 or 67%. This means that the sportsbook believes that the team has a 67% chance of winning.
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Examples
Let’s look at some examples of American odds for different sports betting events.
For an NBA game between the Los Angeles Lakers and the New York Knicks, the odds might be listed as -200 for the Lakers and +180 for the Knicks. This means that the sportsbook believes that the Lakers have a 67% chance of winning, while the Knicks have a 35.7% chance of winning.
For an NFL game between the Philadelphia Eagles and the Dallas Cowboys, the odds might be listed as -120 for the Eagles and +110 for the Cowboys. This means that the sportsbook believes that the Eagles have a 54.5% chance of winning, while the Cowboys have a 47.6% chance of winning.
For an MLB game between the Boston Red Sox and the New York Yankees, the odds might be listed as -140 for the Red Sox and +130 for the Yankees. This means that the sportsbook believes that the Red Sox have a 58.3% chance of winning, while the Yankees have a 43.5% chance of winning.
Conclusion
We hope you now understand how to read American, Decimal, and Fractional odds. Now that all is clearer, why not check out our bet basics odds and lines or player props pages and find today's best bet?