The lines, longest to shortest

Every inch is cut in half, then in half again, down to sixteenths. The longer the line, the simpler the fraction.

Inch — the longest line, with the number.
1/2 — the next longest, dead center.
1/4 and 3/4 — the two medium lines.
1/8 — the short lines between those.
1/16 — the tiny ones. Sixteen to an inch.
1/32 — some tapes squeeze these into the first foot. Framing doesn't use them, so they're left off here.

Reading it fast

Don't count from the inch every time. Find the nearest long line, then count the little ones from there.

That mark is past the 1/2 by three tiny lines: 8 + 3 = 11/16. Or: it's five tiny lines short of the inch: 16 − 5 = 11/16. Same answer, whichever is closer.

Anything past the 1/2, count down from the next inch. 13/16 is "three short." 15/16 is "one short."

The hook wiggles on purpose

The metal hook slides exactly the thickness of itself. Hook it over an edge and it pulls out; push it against a wall and it slides in. Both read true. Don't rivet it tight and don't trust a tape with a bent hook.

Burning an inch: when you can't hook anything, hold the tape at the 1 instead of the 0 and take 1 off what you read. Say it out loud every time. Everyone has cut a board an inch long.

The slot in the hook

That little slot fits over a nail or screw head. Set a nail, hook it, and you can measure alone with the tape anchored.

Hook a nail, hold a pencil at the number you want, swing it around: a perfect circle or arc.

The hook scratches a mark

The bottom edge of the hook is serrated. Drag it back and forth across the wood and it leaves a line. No pencil needed.

A straight line at any distance

Hold a pencil tight against the hook, pinch the tape at the number you want, and slide the whole thing along the edge of the board. You get a line that exact distance in from the edge, the full length.

Subtract on the tape

Fold the blade back on itself so the hook lands on the bigger number. Find the smaller number on the bottom run. The number sitting right on top of it on the folded run is the difference.

Hook on 98 1/4, look at 61 1/8 underneath, the folded tape reads 37 1/8 above it. No math.

Measure up, not down

Floor to ceiling: hook the tape on the floor, put your toe on it, run the blade up the wall and read at the ceiling. Easier than holding the hook up there.

The cut eats 1/8"

The blade turns about 1/8" of wood into dust every cut (a hair less with a thin blade). Mark it, then cut on the waste side and leave the line. Cut on the line and the piece is short.

Cutting a board into pieces? Mark and cut one at a time, measuring from the fresh end. Mark them all from one end first and each piece comes up 1/8" short of the last.

Red numbers and black diamonds

Slide it: red 16 and 32, diamonds at 19.2 and 38.4, the red flag at each foot.

Red every 16" — 16, 32, 48, 64… — stud, joist and rafter layout at 16 on center. Hook the tape, mark the reds, you're laid out.

Black diamonds every 19.2" — five of them in 8 feet. Truss and I-joist layout at 19.2 on center, used when the plans say so.

The foot marks (1F, 2F…) and the inch count both run the whole tape, so 50" and 4' 2" are the same mark.

The blade is 1" wide

Most tapes have a blade that measures 1" wide. Big-blade tapes run 1 1/4". Measure yours once with the tape itself and remember it.

Use it: lay the tape flat and the two edges are a 1" gauge. Quick 1" offset line, a 1" strip to rip, checking a hole, all without reading a number.

Inside measurements

The case has its length printed on it — "3 in." or "82 mm." Push the case into the corner, read the tape at the edge of the case, and add the case length. Bending the tape into the corner and guessing is how windows end up a half short.

Centers and equal spaces

Center of a board: read the length, halve it on the tape — the math tab does this and shows you the mark. For equal spaces (balusters, pickets), it's the length divided by the number of spaces, and the marks are at each multiple. The math tab lays them all out.

Metric, if a plan shows it

1 inch = 25.4 mm. 1 foot = 304.8 mm. A 2×4 is 38 × 89 mm. The other edge of many tapes is marked in millimeters; the math tab converts either way.

Keep it honest

Don't let the tape slam shut. The hook hits the case, bends, and from then on every measurement is off. Stop it with a finger before the hook gets there.

Now and then check a tape against one you trust. If the hook sticks, clean the rivets so it can slide.

What are you doing?