Feet · Inches · Fractions · Pay Once

Your thumbs already know where the keys are.

The feet-inch-fraction calculator with the key layout tradesmen already trust — full rafter, stair, and pitch functions, exact fraction math, no login, no subscription.

The keys sit where your thumbs expect them. Feet, inch, fraction, and the trade functions — one row, safety yellow.

Read the reviews

Your old calculator app now wants $39.99. A year.

The whole category flipped. A trial that expires mid-measure, a login every time you open it, a bill every April for math that hasn't changed since the tape measure. TapeMath is what a tool is supposed to be: buy it once, it works forever — and it works in a basement with no signal, on a jobsite with no bars.

What it does

Built to match the calculator on your belt.

Exact fraction math

12' 6-3/16" ÷ 3 is exact — never 4.1770833. Rational arithmetic under the hood, checked against 150+ published worked examples.

Trade functions

Rafters — common, hip, valley, jack. Stairs. Studs on-center. Board feet. Pitch conversions. The keys are right where you reach for them.

Paperless tape

Every calc logged and scrollable. Tap a line to recall it. Text the whole cut list to the crew before you climb down.

Built for gloves

Big glove-friendly targets. A haptic thump on every keypress — you feel the key on a loud site. Works fully offline.

The price

Same keys. One of these bills you every year.

The subscription calculator apps rent you the layout you already know. TapeMath sells it to you — once — and then it's yours.

The subscription apps TapeMath
Pay once ×
Works offline ×
No login ×
Rafter + stair keys
Exact fraction math
Price $39.99 / year
+ login every use
$9.99 once

The trade keys are table stakes — everyone has them. The only line that really moves is the one at the bottom.

A tape measure doesn't have a monthly fee.
Neither should the math.
Why TapeMath is buy-once
Pricing

Pay once. Works forever.

Free
$0 forever
No account. No card. No catch.
  • Full feet-inch-fraction arithmetic
  • Every unit conversion — ft, in, decimal, metric
  • Fractions to 1/16 display
  • Works offline, no signal needed
TapeMath Pro
$9.99 once
  • Everything in Free
  • Trade functions — rafters, stairs, studs o.c., board feet, pitch
  • Paperless tape — log every calc, text the cut list
  • Finer fractions — 1/32 and 1/64