Feet and Inches Calculator

Add and subtract tape measurements exactly, and read the answer off the tape.

Measurements

Start

= 150" (12' 6")

= 43 5/8" (3' 7 5/8")

= 1/2"

Live

Feet and Inches · Result

Calculated

TOTAL LENGTH

193 1/8" total

Inches
193 1/8"
Decimal feet
16.0938'
Millimetres
4 905.4 mm
On the grid
Yes
Code references & assumptions · 0

How this result is supported

Terms are held as exact fractions and only rounded for display. Where the exact result does not land on the selected grid, the result says so.

Code references and product data are quoted in the units their source uses.

Reference checks are informational, not compliance determinations.

How feet and inches is calculated

Every term is parsed as an exact fraction and kept that way. Nothing becomes a decimal until it is displayed, so a chain of sixteenths does not accumulate the small errors that decimal conversion introduces.

The answer is shown on a tape grid — sixteenths by default — alongside the exact value. When the exact result does not sit on that grid, the calculator says so rather than rounding silently, because a measurement that reads 7″ on the tape but is not quite 7″ is worth knowing about before you cut.

A scale factor multiplies or divides the total once, after the sum. It carries no unit: a bare number or a typed fraction like 2 1/2, never 2″, because a length is not a scale.

total = t₁ ± t₂ ± t₃ …

Terms added or subtracted in order.

scaled = total × factor or total ÷ factor

Applied once, after the sum.

Questions

Why does it say the result is not on the grid?
Because the exact answer falls between two marks on the tape you selected. Dividing 10″ by 3 is the simple case: the true value is 3⅓″, which no sixteenth matches. The displayed figure is rounded to the nearest mark and the exact value is kept alongside it.
Can I use it for cut lists?
Yes, and that is what the exact arithmetic is for. Add your pieces, apply a scale if you are dividing a run into equal parts, and read the result on the grid your tape actually has — the calculator will tell you when a division does not come out evenly on it.