Bike helmets with adjustable fit for a range of head sizes

Which bike helmets offer a wide range of head sizes?

No checked fact states a head-size range that these helmets cover. The closest matches are the fit adjustments and size figures below. Banwood Eco Helmet: The Australian maker page lists weight as 355 g (the UK maker page says 280 g and the store says 0.78 lbs; the sources disagree), and mentions dial-fit, recycled chinstrap and ventilation. The helmet height can be adjusted in three steps. The Australian maker page says ages 3+, head circumference 50–54 cm, and Australian/New Zealand Standards certified; the UK maker page gives ages 2–7 and 52–56 cm, so the age and size figures disagree. Doona Liki Helmet: The helmet has a dial-fit adjustment system for a customized and secure fit. The maker says the helmet is for learning to ride the Liki Trike and for the next size of bicycle until age 4. Banwood Classic Helmet: The helmet height is adjustable in three steps. The XS size is 48–52 cm, approximate age 18 months to 4 years.

ProductWhyFit adjustmentSize or age guidance
1. Banwood Eco Helmet sold by modernnursery.comThe Australian maker page lists weight as 355 g (the UK maker page says 280 g and the store says 0.78 lbs; the sources disagree), and mentions dial-fit, recycled chinstrap and ventilation.The helmet height can be adjusted in three steps. manualThe Australian maker page says ages 3+, head circumference 50–54 cm, and Australian/New Zealand Standards certified; the UK maker page gives ages 2–7 and 52–56 cm, so the age and size figures disagree. guide
2. Doona Liki Helmet sold by megababiesusa.comThe helmet has a dial-fit adjustment system for a customized and secure fit.The helmet has a dial-fit adjustment system for a customized and secure fit. guideThe maker says the helmet is for learning to ride the Liki Trike and for the next size of bicycle until age 4. guide
3. Banwood Classic Helmet sold by modernnursery.comThe helmet height is adjustable in three steps.The helmet height is adjustable in three steps. manualThe XS size is 48–52 cm, approximate age 18 months to 4 years. guide

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Written 2026-10-22T12:14:15.176Z.

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