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US 6 3/4 Hat Size in cm, UK and Letter Size
A US 6 3/4 fitted hat is for a head of 54 cm (21.3 in) around. It is a UK 6 5/8 and usually S in letter sizes.
| Head (cm) | Head (in) | US | UK | Letter |
|---|---|---|---|---|
| 54 | 21.3 | 6 3/4 | 6 5/8 | S |
Good to know
- US fitted sizes are the head circumference in inches divided by π, in eighths. UK sizes run one eighth below US for the same head. EU sizes are the head in centimetres.
- Measure around your head just above the ears and eyebrows. Between sizes, choose the larger one.
Sizes either side
Smaller: 6 5/8Larger: 6 7/8Open the full converterHow to measure yourself
Questions
What is a 54 cm head in US hat size?
US 6 3/4.
What size is a 6 3/4 hat in letters?
Usually S, but letter sizes vary by maker.
What is US 6 3/4 in UK hat size?
UK 6 5/8.
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