EU 55 to US hat size
A EU 55 is a US 6 7/8, a head circumference of 55 cm (21 5/8 in). Convert any other size below, or see the full EU to US chart.
EU sizes near 55
| EU size | US size | Head (cm) | Head (in) |
|---|---|---|---|
| 53 | 6 5/8 | 53 | 20 7/8 |
| 54 | 6 3/4 | 54 | 21 1/4 |
| 55 | 6 7/8 | 55 | 21 5/8 |
| 56 | 7 | 56 | 22 |
| 57 | 7 1/8 | 57 | 22 3/8 |
A EU 55 and a US 6 7/8 both describe a head circumference of 55 cm. The small difference in the printed numbers comes from how each system rounds that circumference, not from any real difference in fit.
For every other EU size, see the full EU to US hat size chart, or measure your head with how to measure hat size.
Common questions
What is EU 55 in US hat size?
A EU 55 is a US 6 7/8. Both fit a head circumference of 55 cm, which is 21 5/8 inches, a letter size S.
How many centimetres is a EU 55 hat?
A EU 55 fits a head of 55 cm (21 5/8 in) around. Measure just above your ears and eyebrows to compare against your own head.
What if I am between two hat sizes?
Round up for comfort, especially for fitted caps that do not stretch much.
Last reviewed and updated on July 2, 2026. Conversion tables are checked against published international sizing standards.