Prefer a desktop app? Same calculator, offline.
Download for Windows / macOS Source on GitHub
Tip: the keyboard works too — digits, + - * /, Enter,
Backspace, Esc, and y / f / i (or ' and
") for units.
On a phone, use your browser's Add to Home Screen to install this page as an app — it keeps working offline.
Made for the tape measure
Working in wood or on a job site means adding and subtracting measurements like 3′ 7-3/8″ — math that decimal calculators make painful. This calculator works the way imperial (SAE) measurements do: enter yards, feet, inches, and fractions directly, and get results in feet and inches with the fraction already reduced. Every computation happens on an exact 1/32 inch grid, so every answer lands on a tape-measure mark. Handy for woodworking, carpentry, framing, quilting, and any DIY project measured in inches.