How to Convert Inches to Decimals

By James Wiley

Inch measurements are most commonly given as mixed numbers, with the whole number of inches listed first and then the remaining fraction after (for example, 4 1/3 inches). Many people want to know how to convert these mixed-number fractions into decimals. The process will only take you a matter of seconds once you know the formula and have a calculator nearby. In addition to inches, this formula can be applied to all measurements whenever you want to convert them from mixed-number form to decimal form.

Step 1

Measure the length or height and write it down (for example, 8 3/8 inches).

Step 2

Divide the top number of the fraction on the right-hand side of the mixed number by its denominator (the number underneath it). Using the example in Step 1, you would divide 3 by 8 and get 0.375.

Step 3

Write the measurement as a decimal, starting with the whole number of inches first, followed by a decimal point and the number you computed in Step 2. For example, 8 3/8 inches would be converted to 8.375 inches.