Hat Sizes Chart
en

Guide

How to measure hat size

Hat sizes are set by the circumference of your head. You only need one good tape measurement — this guide shows exactly where to place it, what to do without a tape, and how to avoid the small errors that lead to the wrong size.

The tape measure method

  1. 01Use a soft tape measure. A tailor's tape or any flexible tape works. A rigid metal tape cannot follow the curve of the head — avoid it, or use the string method below.
  2. 02Place it where the hat sits. The tape crosses the middle of the forehead and passes just above the ears and eyebrows. That is where the inside band of a hat rests, and so it is the only place the measurement is honest.
  3. 03Stay level. The tape may not ride up at the back or dip at the front. Check in a mirror — a tilted tape can read 1–2 cm wrong, enough to move you a full size.
  4. 04Snug, not tight. The tape should touch the hair all around without pressing in or pinching.
  5. 05Read and repeat. Read where the tape meets its start, then measure twice more and keep the largest reading. Enter it in thehat size converter.
Fig.wrapping a soft tape around the head just above the ears, level across the forehead

No tape? The string method

Fig.marking a piece of string, then measuring it flat against a ruler
  1. 01Wrap a piece of string (shoelace, ribbon, phone charging cable) around your head exactly as the tape method describes: above the ears, level, snug but not tight.
  2. 02Mark the crossing point with your fingers or a clip, and do not let the string twist.
  3. 03Measure the string flat against a ruler or a hard measuring tape. That length is your head circumference — enter it in the converter like any other number.
  4. 04Prefer to print? Ourprintable paper measuring tapeprints at true physical size on A4 or Letter paper and includes a calibration check against a bank card.

Four habits for a trustworthy measurement

Measure warm. Heads read slightly larger after exercise or heat; measure when relaxed.

Match your hairstyle. Measure with the hair exactly as it will sit under the hat.

Take the largest of three. Small tape dips produce small numbers; the largest reading is the honest one.

Re-measure before each purchase. Head size changes slowly over the years, and brands differ slightly anyway.

For context: adult heads fall roughly between 53.0 and 65.4 cm in this chart's range — see the full hat sizes chart.

Measuring questions

Where exactly should I measure my head?
Where the hat will actually sit: wrap the tape so it crosses the middle of your forehead and passes just above your ears, level all the way around. Measuring higher or lower changes the number — most hats sit just above the eyebrows.
How accurate is the string method?
Accurate to within a few millimetres if you are careful. Keep the string flat and snug (not stretched), mark the crossing point, then measure the distance against a rigid ruler. Because string is harder to keep level than a soft tape, measuring twice and keeping the larger reading helps.
Should I measure over my hair?
Measure with the hairstyle you will actually wear under the hat. Voluminous or braided hair can add the equivalent of a size, so measure with the hair down (or in its usual style), not flattened for the occasion.
How tight should the tape be?
Snug, not tight. The tape should touch the skin all around without pressing in — the felt of a fitted hat is not elastic, and hats are sewn to the measured circumference, so an over-tight reading will leave you with a loose hat.
Do I measure the same way for a child?
The method is identical, but children's heads grow quickly — measure freshly each time rather than guessing by age. Our kids' hat size chart has age-typical ranges with their data sources, but the advice there is the same: measure the child's head.

Measured? Get your size.

Enter the number and see US, UK, EU and letter sizes instantly.

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