Gap to Old Navy size
The short answer
Gap S is Old Navy XS or S by the two brands' own charts. 4 of 7 Gap sizes land on a different label at Old Navy.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
| Gap | Gap builds it for | Old Navy, by chart | Same label | Old Navy builds it for | Old Navy also prints |
|---|---|---|---|---|---|
| XS | chest 35 to 36 in, neck 13.5 to 14 in, sleeve 31 to 32 in | XS | XS | chest 36 to 37 in, neck 13 to 13.5 in, sleeve 31.5 to 32 in | not published |
| S | chest 37 to 38 in, neck 14 to 14.5 in, sleeve 32 to 33 in | XS or S | S | chest 36 to 37 in, neck 13 to 13.5 in, sleeve 31.5 to 32 in | not published |
| M | chest 39 to 41 in, neck 15 to 15.5 in, sleeve 33 to 34 in | M | M | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 33.5 to 34 in | not published |
| L | chest 42 to 44 in, neck 16 to 16.5 in, sleeve 34 to 35 in | M or L | L | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 33.5 to 34 in | not published |
| XL | chest 45 to 48 in, neck 17 to 17.5 in, sleeve 35 to 35.5 in | L or XL | XL | chest 44 to 46 in, neck 16 to 16.5 in, sleeve 34.5 to 35 in | not published |
| XXL | chest 49 to 52 in, neck 18 to 18.5 in, sleeve 35.5 to 36 in | XL or XXL | XXL | chest 48 to 50 in, neck 17 to 17.5 in, sleeve 35.5 to 36 in | not published |
| XXXL | chest 55 in, neck 18.8 in, sleeve 36.5 in | XXXL | XXXL | chest 55 to 57 in, neck 19 to 19.5 in, sleeve 37.5 to 38 in | not published |
What wearers say
Charts describe a garment, not a fit. We do not collect fit reports for this category yet, so this table is the two brands' own claims and nothing more.
Sources
- Gap size guide, read on 2026-09-18. Gap on TrueToSize
- Old Navy size guide, read on 2026-09-18. Old Navy on TrueToSize