Betting Odds Converter

Input odds in any format to see them converted to American odds, Decimal odds, Fractions, or Probability with this betting odds calculator tool.

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Odds Converter

An odds calculator lets you enter your odds and automatically converts them into decimal, American, and fractional odds. It will also give you the implied probability odds.

Why Do You Need an Odds Converter?

Perhaps you are following a tipster on social media from another part of the world and he is using decimal odds or fractional odds each time he talks about a play he likes. Converting these into American odds will be quite helpful when you are placing your bets as you would likely want to know if the betting odds you are getting are as good as theirs.

On the flip side, if you begin working with modeling involving setting your own implied probability to an outcome, American odds likely won’t suit your purposes, and converting to decimal odds will be a big part of your process. As you’ll read later, decimal odds are the easiest format to convert into implied probability and an odds calculator can be a helpful tool.

How to Use an Odds Converter

Simply enter the price in the odds format you are wanting to convert into the corresponding box. For example: to convert decimal odds to American odds and fractional odds, you would enter the price in the box labeled “decimal” and the other fields will automatically display American odds, fractional odds, and implied probability.

You can even start with implied probability if you want to see what odds correlate with that percentage.

When you are entering American odds, you must be sure to use a minus symbol (-), when entering negative odds. You can use a plus sign if you want for positive odds, but it is not nessecary. If no symbol is used with American odds, the odds coversion will assume the American odds are a positive value when it goes to convert odds.

A Closer Look at Sports Betting Odds Formats

Decimal Odds

Decimal odds are given as a number bigger than one, that tells you how much your return on every dollar would be if you bet wins, including your initial stake. Positive odds are numbers two or larger, while negative odds are numbers between one and two.

Fractional Odds

Fractional odds are displayed as a ratio of your winnings compared to the stake. They are very simple when the odds are based on an integer, but can be a bit more complicated, for example +500 in American odds is simply 5/1 in fractional odds but +525 is 21/4.

An example: 5/1 means you would win five dollars for every dollar staked if your bet wins. These sort of betting odds are often used for horse racing but are often tossed around casually in every day conversations as well.

American Odds

American odds, sometimes referred to as U.S. Odds, are the default odds used by U.S. based sportsbooks and betting sites. They are based on wagering to win $100 for favorites and wagering $100 to win more on underdogs.

For example -130 would mean you need to bet $100 to win $100, while +130 means your $100 bet would win $130.

Working Out Implied Probability Odds

Implied probability is what all odds boil down to. Betting odds are, in escence, a percentage chance to win. If you were to enter +100 into the odds converter, you’d come back with 50% as an implied probability.

If you were to do the calculation yourself, you would want to convert the American odds or fractional odds to decimal odds first, as the formula for implied probability is simple one over the decimal odds. In the previous example, +100 in American odds (1/1 in fractional odds) is 2.00 in decimal odds, and one over two is 1/2, or 50%.