How should a full face MTB helmet fit?

A full face helmet should fit snugly around your entire head with even pressure and no pressure points. The chin bar should sit approximately 1–2 finger widths from your chin and jaw when your mouth is closed—close enough to protect you but with enough standoff for impact absorption. The cheek pads should contact your cheeks without excessive pressure. The visor should not obstruct your upward vision when in the lowered position. When you shake your head vigorously, the helmet should move with your head, not shift independently. Always try on multiple brands as the internal shapes vary significantly.