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 the aptitude test loves 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.

The 1/16" tick hierarchy

Every imperial tape splits an inch into sixteen equal parts. Taller ticks are the rounder fractions. Sign in to keep reading the worked examples.

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Score high. Get called sooner. This test puts you on the Applicant Waiting List. Miss the cutoff and you typically wait 6 to 12 months. Email magic link, no card. Takes about 30 seconds.

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