Add or subtract feet and inches measurements with automatic carry-over. Perfect for construction, carpentry, and home improvement projects.
Last updated: March 2026 | By Patchworkr Team
Working with feet and inches requires special attention because there are 12 inches in a foot. When adding or subtracting measurements, you must "carry over" when inches exceed 12, just like carrying over minutes when they exceed 60.
This calculator automatically handles the conversion, so 5 feet 8 inches + 3 feet 6 inches correctly equals 9 feet 2 inches (not 8 feet 14 inches). This is essential for accurate construction, carpentry, and measurement calculations.
The 12-inch foot comes from ancient measurement systems. Twelve is divisible by 2, 3, 4, and 6, making it practical for dividing measurements into halves, thirds, quarters, and sixths.
Divide the inches by 12 and add to the feet. For example, 5' 6" = 5 + (6÷12) = 5.5 feet. This calculator shows the result in traditional feet and inches format.
Yes! You can enter fractional inches like 6.5 or 3.25. The calculator handles decimals and shows precise results.
Negative results occur when subtracting a larger measurement from a smaller one. The calculator marks negative results with a minus sign (−).
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