Hat Size Converter
Measure your head and convert it to fitted hat sizes in the US, UK and Europe, plus letter sizes.
How to use the Hat Size Converter
- Measure around your head about 1 cm above your ears and eyebrows.
- Enter the measurement in cm or inches.
- Read your hat sizes.
How it works
European hat sizes are simply the head circumference in centimeters. US fitted sizes equal the circumference in inches divided by π (roughly the head’s “diameter”), in eighths: a 57 cm (22⅜ in) head is a US 7⅛. UK sizes run ⅛ smaller than US. If you are between sizes, choose the larger one — hats can be tightened with sizing tape.
Hat size chart
| Head (cm) | Head (in) | US | UK | Letter |
|---|---|---|---|---|
| 54 | 21.26 | 6 ¾ | 6 ⅝ | S |
| 55 | 21.65 | 6 ⅞ | 6 ¾ | S |
| 56 | 22.05 | 7 | 6 ⅞ | M |
| 57 | 22.44 | 7 ⅛ | 7 | M |
| 58 | 22.83 | 7 ¼ | 7 ⅛ | L |
| 59 | 23.23 | 7 ⅜ | 7 ¼ | L |
| 60 | 23.62 | 7 ½ | 7 ⅜ | XL |
| 61 | 24.02 | 7 ⅝ | 7 ½ | XL |
| 62 | 24.41 | 7 ¾ | 7 ⅝ | XXL |
Frequently asked questions
What hat size is 22 inches?
About US 7 (56 cm).
What is the average hat size?
About 7⅛–7¼ (57–58 cm) for adult men and 7 (56 cm) for women.
How do I measure my hat size?
Wrap a soft tape around your head just above the ears and eyebrows.
Are UK and US hat sizes the same?
No — UK sizes are one-eighth smaller.