Enter a number, then choose its unit. Tap 5, ft, 3, ½, in for 5′ 3½″. Quick fractions add to the current number.
Calculate as usual. Use +, −, ×, ÷, then =. Unmarked numbers are inches for addition and subtraction, and act as factors for multiplication and division.
Keep the precision you need. Math stays exact; the precision selector rounds only the displayed inches. ≈ means the displayed value has been rounded. Continued calculations use the exact result.
Use your keyboard, too. Edit the calculation field directly: (5 ft 3 1/2 in + 2 in) / 3. Enter calculates; Escape clears. Type fractions as 3/8, and division as / with spaces.
Area and volume work, too. 8 ft × 3 ft returns 24 ft². Divide by a number to split a measurement; divide by another measurement to get a ratio.
Take it to the site.Use Get the app at the top. Open in Safari on iPhone and choose Share → Add to Home Screen. In Chrome on Android, choose Install app. Wait for “Offline ready” before disconnecting. Calculations and history stay on this device. Browser cleanup can remove saved data; export your tape to keep a backup.