Hat Size Chart
Convert head circumference to common letter and fitted hat sizes.
Sizing hub
Hat Size
Measure around the head and map that measurement to common fitted and letter sizes.
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Hat Size Calculator
Estimate a common hat size from measured head circumference in centimeters.
Hat Size Chart in Inches
Use head circumference in inches to compare common hat sizes.
Hat Size Chart in CM
Use head circumference in centimeters to compare fitted and letter hat sizes.
Fitted Hat Size Chart
Compare fitted cap fractions with measured head circumference and nearby rounded inch references.
Western Hat Size Chart
Use head circumference to estimate common western hat sizes.
Head circumference is the anchor
Measure around the position where the hat will actually sit, keeping the tape level. Fitted fractions and S/M/L labels are derived references rather than direct measurements.
Shape and material affect comfort
Structured caps, flexible bands, wool felt, and other constructions can feel different at the same nominal size. If you fall between sizes, check the maker’s adjustment guidance.
Convert from head circumference, not another hat
Measure around the head and map that measurement to common fitted and letter sizes. Record the circumference before reading a fitted fraction or letter size.
If two sizes are close, construction matters: rigid fitted hats, elastic bands and shapeable hats do not behave the same way.
Method & references
How this guidance is checked
These sources support the measurement method and help check real-world variation. They are not presented as one universal brand-size table.
- New Era Fitted Caps Size Chart — New Era. Fitted-cap circumference cross-check and evidence that label CM values can differ from measured head circumference.
- Men Size Guide — H&M. Cross-check for men’s EU/US clothing, chest and waist ranges, trousers, jackets, and suit-style numeric references.
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