Choosing the right bike size for your child is about more than just comfort; it’s essential for their safety, skill development, and long-term confidence. Whether they’re learning on a balance bike, cruising on a pedal bike with stabilisers, or tearing around on an electric quad bike, the right fit makes all the difference.
This guide will help you measure correctly, understand key sizing charts, and choose the best ride for your little adventurer.
Why getting the right kids’ bike size matters
A bike that’s too small or too big can impact control, cause discomfort, and even lead to avoidable injuries. That’s why sizing a kid’s bike properly from the start helps your child:
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Build confidence while learning to ride
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Develop essential balance and coordination skills
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Ride safely and comfortably
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Stay motivated to ride and explore
How are kids’ bikes sized?
Unlike adult bikes (which are based on bike frame size/height), children’s bikes are sized by wheel diameter, usually ranging from 12” to 26”.
|
Wheel size |
Approx. age range |
Inside leg (cm) |
Rider height (cm) |
|
12” |
2–3 years |
33–41 cm |
85–98 cm |
|
14” |
3–4 years |
36–45 cm |
88–104 cm |
|
16” |
4–5 years |
41–51 cm |
95–110 cm |
|
18” |
5–6 years |
46–56 cm |
112–127 cm |
|
20” |
6–8 years |
53–63 cm |
114–129 cm |
|
24” |
8–10 years |
57–68 cm |
128–143 cm |
|
26” |
9–12 years |
61–81 cm |
135–150 cm |
Top tip: If your child is between sizes, consider their confidence level. Nervous riders may feel more secure on a smaller wheel size at first.
How to measure a child for the right bike size
What you'll need:
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A tape measure
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A flat wall
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Pen & paper
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Your child (ready to stand still!)
Step-by-step:
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Measure height: Have your child stand straight against a wall. Measure from the floor to the top of their head.
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Take an inside leg measurement: While barefoot, measure from the crotch to the floor (or place a book between their legs and measure from the top of the book to the floor).
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Check a bike size chart: Match your child’s height and inside leg with the recommended wheel size.
Different types of kids’ bikes (and what size works best)
Balance bikes (12”–16”)
Ideal for younger children just learning to balance. No pedals, no fuss, just pure focus on developing coordination. Perfect for toddlers and preschoolers.
Bikes with stabilisers (12”–18”)
Great for beginners who want the feel of a regular bike with extra stability. Removable stabilisers let them progress at their own pace.
Pedal bikes (16”–26”)
Once balance is nailed, pedal bikes are the next step. Choose a lightweight bike that suits their strength and height for smoother handling.
Electric bikes & motorbikes (24”–26”)
For older kids and teens who want some thrill. These often suit children aged 8+ and come with built-in speed limiters for safe riding.
Testing the fit: Signs of the right size bike
Before buying, or as soon as the bike arrives:
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Feet should touch the ground flat when seated (for younger children)
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Knees should bend slightly when pedalling
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Arms should reach the handlebars comfortably without stretching
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They should feel in control while riding and turning
Adjust the saddle height and handlebars to fine-tune the fit. A properly sized bike boosts confidence and control, especially when they’re starting out.
Common bike sizing mistakes (and how to avoid them)
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Buying a bike they’ll “grow into” (unsafe and discouraging)
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Skipping the leg length measurement (even tall kids can have short legs)
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Using age alone to determine size (kids grow at different rates)
Pro tip: Always measure before buying a bike for your child. Visit your local bike shop or use a trusted bike size chart for kids.
Shop a range of bikes at Outdoor Toys
From wheel size to bike fit, we've got you covered every pedal of the way at Outdoor Toys. So you can grab a new set of wheels for your little one and have them fall in love with their new ride in no time.
We've also got a range of ride on toys for any little speed demons, from ride on tractors and ride on cars to flashy electric motorbikes and scooters.
Not so fast and furious? No worries, our store is full of exciting toys to whet the appetite of any mini adventurer - including metal swing sets, swimming pools and paddling pools, trampolines and playhouses. So your little ones can get creative and enjoy the glorious world of outdoor play!
FAQs: Bike size guide
What’s the best way to measure a child’s bike size?
Measure the inside leg and refer to a wheel size chart for guidance. Most kids’ bikes are sized by wheel diameter, not frame height.
Can my child try the bike before buying?
If you're shopping in person, yes! Otherwise, measure carefully at home. Many online retailers offer helpful size guides and return policies.
Why is wheel size important?
Wheel size significantly impacts comfort, handling, and safety. Selecting the incorrect size can make riding more challenging and discourage learning.
Can a child ride a bigger bike for longer?
It’s tempting to size up, but a bike that’s too big can be unsafe and hard to control. Stick with the right size now for better learning and confidence.