Feet Inch Fraction Calculator

Tapemath is a feet and inches calculator built for the job site: big keys you can hit with work gloves on, answers written the way a tape measure reads, and a paper tape that keeps every calculation.

FEET, INCHES AND FRACTIONS – EXACT
• Add, subtract, multiply and divide feet, inches and fractions: 5' 7-3/8" + 2' 4-1/2" = 7' 11-7/8".
• Exact fraction maths with no decimal drift. 7/8 is 0.875, not 0.82.
• Divide a board into equal parts: 12' ÷ 5 = 2' 4-13/16". When an answer is rounded you see an ≈ mark and the exact value (28.8").
• Round to the nearest 1/2, 1/4, 1/8, 1/16, 1/32 or 1/64 inch.
• Length × length gives square feet, × depth gives cubic feet, length ÷ length gives a plain number.
• Show answers as feet-inches, inches only, decimal feet, decimal inches, mm, cm or m – a calculator for inches that answers in inches when you work in inches.
• A tape-measure strip under the answer shows exactly where to mark.

METRIC TOO
Switch the keypad to m / cm / mm and mix systems in one sum: 1700 mm = 5' 6-15/16". Every trade calculator works in feet-inches or metric.

CONSTRUCTION CALCULATOR TOOLS – WITH THE FORMULA SHOWN
• Board foot calculator: thickness × width × length ÷ 12 (one board foot is 1" × 12" × 12"). Nominal sizes (2×4) or actual dressed sizes, number of pieces, price per board foot, multi-size lumber orders, cubic feet and cubic metres. A calculator for wood that shows its working, so you can check the order by hand.
• Area and volume: rectangle, circle or triangle; square feet, square yards, cubic yards and m².
• Stairs: number of risers, riser height, treads, total run, stringer length and angle from the total rise. Flags risers over 7-3/4" and treads under 10" (common IRC limits – always check your local code).
• Roof pitch: x/12 ↔ degrees ↔ percent, pitch factor, rafter length with overhang.
• Concrete: slab, footing or round column; cubic yards with a waste allowance, ready-mix order and 40, 60 and 80 lb bag counts.

PAPER TAPE AND MEMORY
Every answer prints on a paper tape, like a printing calculator. Tap a line to reuse its exact value, copy it or share it. M+, M− and MR memory keys. Tap the answer to copy it; hold the display to paste a measurement.

BUILT FOR GLOVES AND SUNLIGHT
Chunky keys with a firm tap, high-contrast safety-yellow and graphite colours, monospaced figures that line up, and a high-contrast Night Shift theme for dark sites.

NO ADS. NO SUBSCRIPTION.
Tapemath has no ads at all: no banner under the keypad, no pop-ups, nothing in the way of your answer. The calculator, the paper tape and every trade calculator are free to use, and nothing renews or expires.

PRO – ONE-TIME PURCHASE
• Saved projects: keep each job's measurements and results together, and share them as text or a CSV spreadsheet.
• Pay once. No subscription.

PRIVATE AND OFFLINE
No account and no sign-up. The calculator works offline and the app does not ask for internet access. Your tape and projects stay on your phone.

Made for carpenters, framers, contractors, cabinet makers, woodworkers, remodelers and DIYers who need a fraction calculator for inches that just works.