Odds Conversion Formulas

We’ll look here at the mathematics behind converting odds from Decimal to American format, and vice versa. 

American to Decimal 

Positive Odds (“+”): Divide the moneyline by 100 and add 1. 

     decimal = (moneyline/100) +1 

Examples:

• +100: (100/100) + 1 = 1 + 1 = 2.00 
• +235: (235/100) + 1 = 2.35 + 1 = 3.35 

Negative Odds (“-“): The conversion is performed by dividing 100 by the moneyline, then adding this value to 1.00. 

      decimal = (100/moneyline) + 1 

Examples:

• -110: (100/110) +1 = 1 + 0.9091 = 1.9091 
• -152: (100/152) +1 = 1 + 0.6579 = 1.6579 

Decimal to American 

To convert a decimal of 2.00 or higher: 

       moneyline = (decimal – 1) *100 

Examples:

• 2.00: (2.00 – 1)*100 = 1*100 = +100 
• 3.35: (3.35 – 1)*100 = 2.35*100 = +235 

To convert a decimal of less than 2.00: 

      moneyline = (-100) / (decimal -1) 

Examples:

• 1.9091 : (-100)/(1.9091 – 1) = (-100)/(0.9091) = -109.99 = -110 
• 1.6579 : (-100)/(1.6579 – 1) = (-100)/(0.6579) = -151.98 = -152