How do I calculate odds ratio?
Sports betting odds tell us a great deal, including the likelihood of an event happening. It takes a little calculating to figure out the probability from a standard listing, but there are simple formulas you can follow. Here’s an example using the money line:
Favorites: Value of Odds/(Value of Odds +100) x 100 = Probability
Underdogs: 100/(Value of Odds + 100) x 100 = Probability
For the above formulas, simply plug in the odds value and work through the calculation. Examples: On a favorite with odds of -130, you would use the number 130 without the minus sign. For an underdog with odds of +120, use the number 120 without the plus sign.