Kids · Boys'
Size-matched helmets for 8 year olds, with color and style notes typically preferred by boys in this age range. Fit remains the priority — pattern and color second.
Open the helmets calculatorEight is a pivotal age for bike sizing — most children this age are on a 20" bike and approaching the transition to 24" wheels. Average-height 8-year-olds (125–130 cm) ride a 20" bike well, while taller children (131+ cm) may be ready for a 24" bike. This is the age where gears become genuinely useful: many 8-year-olds ride longer distances, explore trails, and tackle hills. A 1x7 or 1x8 drivetrain is the best introduction. Hand brakes should be the sole braking system by now, with both front and rear brakes operational. Disc brakes are a nice upgrade if the budget allows — they provide better stopping power in wet conditions and require less hand strength than rim brakes.
Measure head circumference at the widest point across the forehead. Most brands size: XS (50–53 cm), S (53–56 cm), M (56–59 cm), L (59–62 cm), XL (62+ cm). Kids helmets typically start at 47–50 cm. Always try before buying; fit varies by brand.
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Giro
S 51–55 cm, M 55–59 cm, L 59–63 cm
Bell
S 52–56 cm, M 56–60 cm, L 60–64 cm
Smith
S 51–55 cm, M 55–59 cm, L 59–63 cm
Poc
S 50–54 cm, M 54–58 cm, L 58–62 cm
Lazer
S 50–54 cm, M 54–58 cm, L 58–62 cm
Kask
S 50–54 cm, M 54–58 cm, L 58–62 cm
Troy Lee Designs
S 53–56 cm, M 56–59 cm, L 59–62 cm
Abus
S 52–58 cm, M 58–64 cm
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