American to Fractional Odds Converter

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How to Use Our American to Fractional Odds Converter

To use our American to Fractional Odds converter, simply enter your American odds in the "Odds" input field.

The tool will automatically output your Fractional odds after you've input valid odds.

It's also possible to change the "From Odds Format" and "To Odds Format".

Lastly, you may also want to check out our odds converter which let's you convert between Decimal, American, Fractional, Implied Probability, Hong Kong, Malaysian, and Indonesian odds all from one page!

How to Convert American odds to Fractional odds

To convert American odds to Fractional odds:

For positive American odds, divide the American odds by 100, turn the decimal into a fraction, and find the simplest form of the fraction. Example for +200 American odds: 200 / 100 = 2/1

For negative American odds, divide -100 by the American odds. Example for -200 American odds: -100 / -200 = 0.5/1 or 1/2

American odds and Fractional odds Explained

Here are the basics of American odds and Fractional odds.

American Odds

As you'd suspect, American odds are the primary format used in the United States. Odds in this format are expressed as a number greater than or equal to +100 or less than -100.

  • American odds greater than +100 are underdogs. The larger the number, the less likely a result is to occur. +110 is a relatively slight underdog with a 47.62% implied probability to win, while +300 odds imply only a 25% chance. You stand to profit $110 if you bet $100 at +110 odds or $300 if you bet $100 at +300 odds.
  • American odds less than -100 are favorites. The smaller the number, the higher the implied probability a side has to win. -110 is a slight favorite with a 52.36% implied probability, while -300 implies a 75% chance. You must risk $110 to potentially profit $100 at -110 odds, and you'd have to risk $300 to potentially profit $100 at -300 odds.
  • American odds at exactly +100 (or -100) have an implied probability of 50%. A +100 bet pays out even money, so if you bet $100 at +100, you stand to profit $100.

Fractional Odds

Most popular in the United Kingdom and Ireland, fractional odds are expressed as a fraction where the denominator is the amount bet, and the numerator is your potential winnings. For example, if you win a bet placed at 1/3 odds, you'll profit $1 for every $3 bet.

Fraction odds are also commonly used in the United States for horse racing.

  • Fractional odds greater than 1 are underdogs, with larger fractions having a lower implied probability. 11/10 has an implied probability of 47.62% and 3/1 is 25%.
  • Fractional odds less than 1 are favorites, with smaller fractions having a higher implied probability. 10/11 is an implied probability of 52.38% and 1/3 is 75%.
  • 1/1 has an implied probability of exactly 50%.

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