Pit to pit size chart and lookup

A 22″ pit to pit is a Large in six of the eight blank styles ShirtMath holds published specs for: Gildan G500 and 5400, Bella+Canvas 3001C, Champion T525C, Hanes 5250T and Next Level 3600 all publish exactly 22.0″ at L. Comfort Colors’ C4017 Large is 22.5″. On the ladies’ Gildan G500L, 22″ sits exactly between XL (21.0″) and 2XL (23.0″). Doubled, it is roughly a 44″ garment circumference. The pit to pit size chart below runs 16″ to 26″; the lookup takes 14″ to 30″.

Type the width you measured across a shirt laid flat. You get the nearest size in each style, the gap, and what the match is worth.

The same lookup in half-inch steps. Five styles publish identical chest specs here and share a column: Gildan G500 and 5400, Bella+Canvas 3001C, Champion T525C, Hanes 5250T. Two letters mean your width falls between those sizes; a dash means nothing within an inch.

Down a column the 2.0″ grade shows itself: every second row is a tie. Across, the C4017 sits half an inch wide of the pack everywhere; the 3600 carries an XS at 17.5″. Body lengths are on the t-shirt size chart; which blank runs biggest ranks all eight.

A lookup that answers with one letter is lying by omission. Each label weighs your number against the published spec and that brand’s stated tolerance.

Exact. The published chest for that size is your number, variance included.

Within ±0.3 or ±0.8. The gap is under that brand’s stated manufacturing variance: on paper, indistinguishable.

Between sizes. Two sizes sit equidistant. No pick is correct, only a direction: smaller wears closer, larger roomier.

Nearest only. A real gap — over tolerance, under an inch. Let length and shoulder decide.

Out of range. Nothing published within an inch; the tool names the closest anyway, with the distance.

A shirt on a table is a tube pressed flat, so the distance around it is the width twice: 22.0″ becomes about 44.0″. That assumes matching front and back panels and ignores the fabric taken at the folded edges — fine for comparing garments, wrong as a body measurement. Your chest is smaller than the tube it moves inside, and the surplus is wearing ease. Work flat to flat: measure a shirt that fits and compare, which is what the shirt size calculator does with chest and length.

Sellers on eBay, Depop and Grailed quote it because nobody can try the shirt on, and vintage tags are long gone. A flat width survives decades and dead brands; a letter does not.

The number carries the seller’s technique. Ask where the tape crossed — at the pit points, or the industry line an inch below the armhole this catalog uses — and whether the shirt lay flat and slack. The pit to pit measurement guide covers both. The other half of the problem is letters drifting away from fixed measurements — vanity sizing, and why these sizing tools start from an inch value.