Measure your head, use the model's chart and check the fit before buying. Between two sizes, the letter alone does not decide which is suitable.
Shark size chart
Reference from the official Shark website, checked on 17 October 2026. Head circumference; inches calculated from centimetres and rounded to one decimal.
| Talla / Size | cm | in |
|---|---|---|
| XS | 53–54 | 20.9–21.3 |
| S | 55–56 | 21.7–22.0 |
| M | 57–58 | 22.4–22.8 |
| L | 59–60 | 23.2–23.6 |
| XL | 61–62 | 24.0–24.4 |
Shark XXL depends on the model
- Aeron GP, D-Skwal 3, Ridill 2 and Skwal i3: XXL 63–64 cm.
- Spartan GT Pro, Spartan RS, RS Jet and OXO: XXL 63 cm in the current chart.
- Race-R Pro, Race-R Pro GP, GP 06 and GP FIM: no XXL is listed.
Do not automatically apply the Spartan GT Pro chart to the older Spartan GT. Check the reference and manual for the helmet you intend to buy.
How to measure
Use a flexible tape around the widest part of your head and repeat if it moves. Follow the manufacturer's positioning instructions; Shoei’s manual places it about 2 cm above your eyebrows and where your ears join your head.
Between two sizes?
For example, 58.5 cm falls between M and L in these ranges. Shark generally suggests starting with the smaller size, but the helmet must hold firmly without pain. Compare both in the same model: a pressure point in one and looseness in another may call for a different model or professional help rather than simply sizing up. Do not expect a painful fit to resolve with use.
Do not infer fit from the category
We do not assume all sport helmets are tighter or all touring helmets roomier. Try the version for your market and do not apply one model's fit to the whole brand.
Check the fit before deciding
- Position the helmet correctly and fasten the strap. Contact should be firm and even, without pain or pressure points.
- Hold it and gently move it sideways and up/down: your skin should follow it rather than the helmet sliding freely.
- Follow the retention check in the manual; if it can come off with the strap correctly adjusted, do not use it that way. Ask a specialist retailer for help.
- Keep it on for a few minutes and try your usual glasses. A short fitting cannot guarantee comfort throughout a journey.
What to compare next
Once fit is confirmed, see our Shark helmet comparison and general sizing guide. This update corrects fitting advice; it is not based on our own physical testing.
Sources: official chart linked above and Shoei wearing manual. Updated 17 October 2026: replaced the automatic smaller-size purchase recommendation and category-wide fit claims.
