You need a flexible tape measure, or a piece of non-stretch string and a ruler. Measure around the part of your head where the hat’s band will sit, then compare that circumference with the manufacturer’s chart.
Measure where you will wear the hat
Pass the tape around your head, usually just above the ears and across the forehead where the band feels natural. Keep it level and snug without pressing into your skin. A hat worn tilted back may sit differently from a cap worn low, so consider the actual style.
Repeat the measurement. If you use string, mark where the ends meet and lay it straight against a ruler without stretching it. Record the circumference in centimetres; divide by 2.54 if a chart uses inches.
Read the maker’s chart
A letter size such as M is not consistent across every brand. Some fitted hats use numerical sizes, while adjustable hats provide a range. Check the chart for the specific product rather than borrowing a conversion from another shop.
If your measurement falls between sizes, follow the seller’s guidance. Choosing a larger size automatically can leave a hat that slips, while sizing down can create pressure. Ask whether that model has an adjustable band or suitable fitting options.
What a comfortable fit feels like
The band should feel secure without digging in. Move your head gently and check whether the hat slides or feels unstable. Look at the crown as well: a hat can have the right circumference but still sit awkwardly because of its height or shape.
Buying online
- Check the listed circumference or adjustable range.
- Look for a clear photograph of the inner band.
- Read the material and care information.
- Check returns before trying to reshape or alter it.
Hair volume and how you wear your hair can affect fit. Measure in a way that reflects how you plan to wear the hat.
Choose a style after you know the size
Once the fit is settled, compare a cap, bucket hat or brimmed style with the clothes you wear most. Our hat styling guide offers a few straightforward combinations. CHOOS is a shopping guide, not the hat manufacturer; product-specific fitting questions should go to the seller.