Centimetres
What size hat is 55 cm?
A head circumference of 55 cm (21.7 in) matches the following fitted size and letter band.
A 55 cm head takes US fitted hat size 6 7/8 (head circumference 21 5/8 inches, UK size 6 3/4, EU 55, letter roughly S).
US fitted
6 7/8
for a 55 cm head
In cm…
55
= 21.7
UK size
6 3/4
= US minus 1/8
EU size
55
≠ 55 — EU rounds the chart row's cm
Sizes near 55 cm
| US | UK | Head (cm) | Head (inches) | EU | Letter |
|---|---|---|---|---|---|
| 6 3/4 hat size | 6 5/8 | 53.9 | 21 1/4 | 54 | S |
| 6 7/8 hat size | 6 3/4 | 54.9 | 21 5/8 | 55 | S |
| 7 hat size | 6 7/8 | 55.8 | 22 | 56 | M |
Check any measurement
The converter turns cm or inches into every hat system, live as you type.