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Calculator

The four operators on real dimensions — entry rules, exact rational math, clear and backspace, and plain-language errors that refuse bad input instead of guessing.

Calculator

The calculator adds, subtracts, multiplies, and divides dimensions — not plain numbers. 7′ 9 5/8″ + 4′ 11 3/16″ is a first-class operation, not a conversion exercise.

Exact all the way through

ConstructionPal computes with exact rational arithmetic. A 5/8 stays 5/8 through every intermediate step; rounding happens once, at display, to your chosen smallest fraction. Two consequences that matter on the job:

  • Repeated operations don't accumulate drift — ten cuts at 3/16″ add up to exactly what they should.
  • The stored value is never the rounded value. Change the fraction setting later and the answer re-displays from the exact stored result.

Entry rules

  • Enter what the tape says: feet, inches, and fractional inches in one value.
  • Decimal inches accepted to four places — 4.75″ works alongside 4 3/4″.
  • Clear empties the current entry; backspace removes the last digit.
  • Negative results are allowed where mathematically valid (a subtraction that goes below zero shows negative rather than refusing).
  • Invalid input is blocked at entry with a plain-language reason — the app tells you what's wrong instead of computing something you didn't ask for.

What it won't do

The calculator never silently coerces a bad entry into a guess, never rounds mid-calculation, and never locks an operator behind payment. All four operators work for every user during the trial, and for every unlocked owner forever — there is no per-operator paywall.

Where to go next