Measure your head, pick a brand, get your size — then read the fit guidance, because the chart is only the starting point.
The big four line up almost exactly — the real fit difference between brands is shell shape, not the chart. Your result is highlighted in the table.
Wrap a flexible tape measure around your head about one inch (2.5 cm) above your eyebrows, over the widest part of the back of your head. Take several measurements and use the largest one. No tape? Use a string, then measure the string against a ruler.
58 cm is a Medium on the standard Shoei, Arai, HJC, and Bell charts. If your head is 56.5 cm, you're between Small and Medium — try the smaller size first.
Yes — snug all around, with even pressure and no movement when you shake your head. Liners compress 10–15% with wear, so a helmet that feels "perfect" in the store often ends up loose. Painful hot spots are not normal, though — that's a shape mismatch.
Their published charts are nearly identical, but some model lines shift the chart (HJC RPHA, Bell Bullitt). The bigger difference is shell shape: round oval, intermediate oval, and long oval. Two helmets in the same size from different brands can fit very differently.
About every five years from first use, and immediately after any crash — even a drop-free "minor" one, because the EPS foam crushes once. Full guide →
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