US to UK Hat Size Conversion
| US | UK |
|---|---|
| 6 3/4 | 6 3/4 |
| 6 7/8 | 6 7/8 |
| 7 | 7 |
| 7 1/8 | 7 1/8 |
| 7 1/4 | 7 1/4 |
| 7 3/8 | 7 3/8 |
Sizing conventions vary by brand and by cut — this table shows the standard published conversion. Always check the garment's own size chart when one is available. See how these tables are compiled.
US and UK hats are cut to the same fractional-inch head-circumference scale, so a US 7 1/8 and a UK 7 1/8 describe the identical head — this page exists mainly to confirm that a retailer has not relisted the same measurement under a number that merely looks different.
UK and European retailers are more likely than US ones to print the centimetre figure alongside the fractional-inch size, which is worth checking against a tape-measured head circumference specifically for a made-to-fit style like a flat cap, where there is little give in the construction.
Frequently asked questions
Is there a genuine sizing difference between US and UK hats?
No — both use the same fractional-inch head measurement. A perceived difference usually comes from a UK listing also showing the EU centimetre size, not from an actual US/UK sizing gap.