Shirt Collar Size Converter: Inches, cm, EU, UK/US
Convert a shirt collar or neck size between inches, centimeters, EU, and UK/US sizing.
Type any one and the rest update instantly.
Type in any field — the others update instantly.
Shirt collar sizes measure the circumference of the neck, but different countries express this measurement in different units and scales.
Inches (UK / US) The traditional Anglo-American system. Collar size equals neck circumference in inches. Common sizes: 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18. UK and US collar sizing is identical — both use inches.
EU Collar Size (European / Continental) Common in Europe and most other countries. Collar size equals neck circumference in centimeters. Common sizes: 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46. A size 40 EU shirt fits a 40 cm (15.75 inch) neck.
Centimeters The raw measurement in metric units. EU collar size and centimeter measurement are the same value. EU size 40 = 40 cm neck circumference.
Conversion formula:
- Inches → cm: multiply by 2.54
- cm → Inches: multiply by 0.3937
- EU size = neck circumference in cm (EU size and cm are identical)
- UK/US size = neck circumference in inches
How to measure your neck: Wrap a soft tape measure around the base of your neck, where a collar would sit. Keep one finger between the tape and your neck for comfort. Add 0.5 inches (1.3 cm) if you want a looser fit.
Common collar size conversions:
| UK/US (in) | EU | cm |
|---|---|---|
| 14 | 35.5 | 35.6 |
| 14.5 | 37 | 36.8 |
| 15 | 38 | 38.1 |
| 15.5 | 39 | 39.4 |
| 16 | 41 | 40.6 |
| 16.5 | 42 | 41.9 |
| 17 | 43 | 43.2 |
| 17.5 | 44.5 | 44.5 |
| 18 | 46 | 45.7 |
Note: EU sizes are sometimes rounded to the nearest whole centimeter on clothing labels. Always try shirts on when possible, as fit varies by brand and cut.
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