Kids · Girls'
Size-matched helmets for 11 year olds, with color and style notes typically preferred by girls in this age range. Fit remains the priority — pattern and color second.
Open the helmets calculatorEleven-year-olds sit right at the crossroads between kids and adult bikes. Most children this age fit a 26" kids bike, and taller 11-year-olds (over 148 cm) may fit an adult XS or S frame with 26" or 27.5" wheels. This transition requires careful attention to more than just wheel size — crank length, handlebar width, brake lever reach, and saddle width all differ between kids and adult bikes. Choosing a kids-specific 26" bike is usually the better option unless your child is large and experienced enough for adult proportions. At 11, most riders benefit from a 1x9 or 1x10 drivetrain, disc brakes, and a bike matched to their preferred riding style. This is the age where specialization makes sense: road, mountain, hybrid, or BMX.
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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