TYLER MILLER LONDON · THE CRAFTSMAN'S GUIDE
The Hat Sizing Guide
A proper fit begins with a proper measurement.
Whether you're commissioning a bespoke cap or simply trying to understand your hat size, this guide will help you find your head measurement and compare modern centimetres with traditional British and American sizing.
How to Measure Your Head
- Use a soft tape measure. A flexible tailor's tape is ideal. If you don't have one, use a piece of string and measure it against a ruler afterwards.
- Find where your cap will sit. Place the tape around your head, just above your eyebrows, above your ears and around the fullest part at the back. Keep the tape level and follow the line where you naturally wear your cap.
- Measure comfortably. Keep the tape snug, but do not pull it tight or compress your hair. It should feel like the fit you want from your cap.
- Check it twice. Repeat the measurement two or three times and note the result in centimetres, ideally to the nearest millimetre (for example, 57.4 cm).
A note from the maker: Please send me your actual head measurement rather than adding extra room yourself. I will take the style, construction and intended fit into account when making your bespoke cap.
Traditional & Modern Hat Size Conversion
The chart below shows approximate equivalents. British (UK) and American (US) numbered hat sizes follow different scales. Letter sizes vary between brands, so centimetres are always the most reliable starting point.
| Centimetres | Traditional UK | Traditional US | Letter size |
|---|---|---|---|
| 52 cm | 6⅜ | 6½ | XS |
| 53 cm | 6½ | 6⅝ | XS |
| 54 cm | 6⅝ | 6¾ | S |
| 55 cm | 6¾ | 6⅞ | S |
| 56 cm | 6⅞ | 7 | M |
| 57 cm | 7 | 7⅛ | M |
| 58 cm | 7⅛ | 7¼ | L |
| 59 cm | 7¼ | 7⅜ | L |
| 60 cm | 7⅜ | 7½ | XL |
| 61 cm | 7½ | 7⅝ | XL |
| 62 cm | 7⅝ | 7¾ | XXL |
| 63 cm | 7¾ | 7⅞ | XXL |
| 64 cm | 7⅞ | 8 | XXXL |
Conversion chart is a guide, not a guarantee of fit. Traditional sizes are rounded to familiar ⅛-size increments. XS–XXXL groupings are indicative and may differ between manufacturers.
What if You're Between Sizes?
If your measurement falls between the whole-centimetre values in the chart, don't guess. For a bespoke cap, tell me the exact figure—for example, 58.5 cm—and let me know whether you prefer a close or relaxed fit. There is no need to round up or down yourself.
A Few Useful Fitting Tips
- Measure in front of a mirror, or ask someone to help keep the tape level.
- Measure where you actually intend to wear your cap; different positions can produce different readings.
- If you have thick hair, measure with your hair as you would normally wear it beneath the cap.
- A cap should feel secure and comfortable, without leaving an uncomfortable pressure mark.
Commissioning Your Bespoke Cap
When you commission a cap from Tyler Miller London, we'll discuss your style, fabric, head measurement and any personal touches before I begin making it. You don't need to know your old UK or US size: your measurement in centimetres is what matters most.
Made with purpose. Worn with character.
Tyler Miller
British Master Hatter