Size breakdown
6 7/8 hat size in cm and inches
US 6 7/8 is an eighth-size fitted label: 21 5/8 inches of head circumference, or 54.9 cm in metric.
US fitted
6 7/8
circumference 21 5/8 in ÷ π
Head circumference
54.9 cm
= 21 5/8
UK size
6 3/4
= US minus 1/8
EU size
55
= cm rounded
Letter size: about S. S.A head measured up to 0.3 cm from 54.9 cm matches this size; between sizes, take the next size up for a non-adjustable hat.Letter sizes vary by brand; check the brand's own chart.
Where 6 7/8 sits on the hat sizes chart
This size and its neighbours, so you can compare at a glance:
| 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 |
Not sure it's your size?
Measure your head and the converter will match you instantly.