Feet and Inches Calculator
Add or subtract feet and inches measurements for construction, woodworking and DIY. Get the result in feet-inches, inches and cm.
Last reviewed by the Radiatus Cloud team
Add or subtract feet-and-inches measurements for DIY and construction.
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Add and subtract feet and inches
Working in feet and inches makes arithmetic awkward because inches carry over to feet at twelve, not ten. This calculator adds or subtracts two feet-and-inches measurements for you and gives the result in feet and inches, total inches, total feet and centimetres. It is built for construction, carpentry, woodworking and home DIY, where measurements are added up and differences worked out constantly.
Each measurement is converted to total inches, combined, and converted back, so the carrying between inches and feet is handled automatically.
Measurement math made easy
Tasks like totalling the lengths of boards, finding the gap left in a run, or working out an offset all require adding or subtracting mixed feet-and-inches figures, which is error-prone by hand. The calculator removes the mental arithmetic and the risk of mistakes. It also gives the metric equivalent, useful when your materials or plans mix unit systems.
Subtraction can produce a negative result if the second measurement is larger, which the tool shows clearly. All calculation happens locally in your browser.
Notes on this tool
Because the feet and inches calculator runs entirely in your browser, you can change the inputs and see the result update immediately, with nothing uploaded and no sign-up required. Everything is computed locally, so your information stays private on your own device, and you can use the tool as often as you like for free.
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Frequently Asked Questions
Why is feet-and-inches math tricky?
Because inches roll over to feet at twelve, not ten, so adding and subtracting requires careful carrying that is easy to get wrong by hand.
What units does it output?
The result in feet and inches, plus total inches, total feet and centimetres, so you can use whichever unit you need.
Can the result be negative?
Yes. If you subtract a larger measurement from a smaller one, the tool shows a negative result clearly.
Who is this calculator for?
Anyone working in feet and inches, especially in construction, carpentry, woodworking and home DIY projects.
Privacy & Security
Everything runs in your browser; nothing is uploaded.
How to Use
Enter two feet-and-inches measurements and choose add or subtract.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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