Odds Converter and Probability Calculator

A quick, simple tool to convert fractional, decimal and American odds. Converts odds from fractional to decimal and also calculates your win/lose probability when entering back and lay odds. Can be used for bookmakers that don't offer a change in odds preference / any offer.

To convert decimal odds to fractional, subtract 1.00 and then find the nearest whole integer (so for example 3.75 - 1.00 becomes 2.75/1, or 11/4).

To convert US odds to decimal, if the US odds are positive, divide by 100 and add 1. If it is negative, divide 100 by the US odds (without the minus sign) and add 1.

To convert fractional odds to decimal, divide the first figure by the second figure add 1.00 (so 11/4 = 2.75, then add 1.00 = 3.75).