Find your helmet size from your head measurement in seconds. Enter your head circumference to get your helmet size from XS to XXL plus the matching hat size. Sizes are approximate and vary by brand, so always try a helmet on where possible.
How to Use
- Wrap a soft tape measure around your head, about 2.5 cm above your eyebrows.
- Enter the measurement and choose centimetres or inches.
- Press Find my size.
- Use the helmet size and hat size as a starting point when shopping.
Key Features
- XS to XXL covered — full adult helmet size range.
- Hat size included — handy for caps and beanies too.
- Dual units — enter and read results in cm or inches.
- 100% private — runs entirely in your browser; nothing is sent or stored.
FAQs
Are these sizes exact?
No — they are approximate. Helmet shells and padding vary by brand, so always try a helmet on where possible.
How should a helmet fit?
It should sit level on your head and feel snug all round, with no pressure points and no rocking when you shake your head.
What if I am between sizes?
Try the smaller size first — helmet padding beds in slightly with wear. If it feels tight rather than snug, go up a size.
Is my data sent anywhere?
No. Everything runs entirely in your browser and never transmits or saves your entries.
Related Tools
Try these related tools: Hat Size Converter, Glove Size Converter, Shoe Size Converter.