Trade Math · Tape Measure
How to read a tape measure to 1/16 inch
The tape measure is a plumber's most-used tool and the math question UA aptitude tests love to put in your way. Here's the tick-mark hierarchy, the fraction patterns, and the three mistakes that cost applicants the most points.
Cheat sheet
- 5 tick heights from tallest to shortest: 1", 1/2, 1/4, 1/8, 1/16
- Count sixteenths from 0 — every tick is 1/16. Divide once you've counted.
- Reduce fractions by their greatest common factor: 8/16 = 1/2, 6/16 = 3/8, 4/16 = 1/4.
- Don't round to the nearest eighth — every 1/16 reading is testable.
Sign in to keep reading
The rest of the tape measure guide is free — after a quick sign-in
Worked examples, the interactive element, and the practice quiz are available to anyone with a free account. Email magic link, no password. Takes about 30 seconds.
No credit card. The diagnostic is free and so is this guide — we just ask for your email so we can save your progress.