Size grading

Size grading is the rule a manufacturer applies to every measurement point as a shirt size steps up: chest, body length, and sleeve all grow by a set increment per size, not by a random amount. On a standard crew like the Gildan 5000, that's roughly 2 inches of chest width per size from Small through 5XL, paired with about 3/4 inch to 1 inch of added body length at each step. Youth and ladies' cuts usually grade tighter, closer to 1.5 inches of chest per size, because those runs cover a narrower band of bodies to begin with.

For a buyer, grading explains why a 2XL polo isn't just a scaled-up Large — it's wider through the chest and longer in the body, but the collar, sleeve opening, and shoulder seam don't expand at the same rate. We've had a client order a 12-piece staff run of Port Authority polos with one left-chest logo and be surprised the placement read slightly higher relative to the collar on the smalls and slightly lower on the 3XLs, purely because length grades faster than shoulder width.

Before quoting a design across a full size run, especially one anchored to a pocket or a yoke seam, pull the brand's actual grading table rather than guessing. A shirt that grades in half-inch chest steps will hold its proportions across sizes far better than one grading in full-inch jumps.

The mistake buyers make constantly is assuming a size run scales evenly, as if a 3XL is simply a doubled Medium. It isn't — size grading adds fixed amounts per step, which pushes the top of a run toward wider and boxier rather than taller and leaner. Check real measurements before promising identical placement across ten sizes.