Tool

Tape Measure Calculator

Add, subtract, multiply, and divide measurements in feet, inches, and fractions — down to the sixteenth. Results come back as an exact fraction, a decimal, and feet + inches.

Tap the + / − button on any row to add or subtract it.

Total

0"

Decimal: 0" Feet+in: 0"

How to do it by hand

The tape splits each inch into sixteenths (1/16). To add or subtract, the trick is to convert everything to sixteenths, add, then simplify again:

  1. 3/8" = 6/16"   and   1/4" = 4/16"
  2. 6/16 + 4/16 = 10/16
  3. Simplify: 10/16 = 5/8"

Multiplying or dividing? A measurement times a plain number scales the length (5 boards of 2 3/8" = 11 7/8"). Two measurements multiplied give an area in square feet. When a result lands between two marks, the tape can't show it exactly — this tool flags that with ≈ and rounds to the nearest 1/16.

Not sure about the simplifying step? Review fractions from scratch →