Hat Size Calculator
Unit ConversionConverts head circumference into hat sizes across international, US, and UK sizing systems.
International Size
The international letter size (XS-XXL).
US Size
7 1/2
The equivalent US fractional hat size.
UK Size
7 3/8
The equivalent UK fractional hat size.
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Creators
Odeh Ahwal0people find this calculator helpful
Views
Helpful
Saved
Embeds
Unit Conversion calculators
Frequently Asked Questions
Why is hat size not just my head circumference in inches?
Hat sizing uses a non-linear scale historically based on hat-block diameters, not a direct inches-to-size conversion, so sizes are matched from a standardized chart rather than computed with a simple formula.
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