Our #1 kids bike sizing tip
Choose a bike based on current fit as well as future growth. Kids should be able to ride their new bike right away— waiting too long to grow into it can cause a loss of interest. The bike should accommodate your child as they get taller, including the ability to raise the seat height and/or handlebar stem.
Start with their height
Start off by measuring your child’s height. Have them stand tall with their back against the wall, looking straight ahead. Use a pencil to mark the wall above their head.
Get their inseam measurement
Save some time and quickly take their leg inseam measurement, too. Standing in the same position, have them hold a book between their legs with the book’s spine meeting their crotch. The distance from top of the spine down to the floor is the leg inseam.
Matching leg inseam length to bike size ensures that your child can comfortably stand over the bike. Confirm there is about 1” or 2” of space between the top tube and their crotch while straddling the bike. This way, they can easily get on the bike or hop off the saddle in case of a sudden stop.
Take confidence into account
Consider your child’s riding ability to check if they can handle a larger wheel size. If they are close to the next bike size, they are probably ready to size up— even more so if they are already strong riders that feel confident making turns and stopping quickly.
Please use BMX bike sizing as a guide only. Size guide does not take into account skill level or riding preference, so you may need to get a longer or shorter top tube length to suit your style of riding.
All bikes below have 20" wheels, which makes the top tube length the determining factor for optimum sizing.
BMX bikes with 22" - 27.5" wheels suit riders of many sizes, but can be more practical for taller riders.
Rider Height Wheel Size 170cm + 22" and up