What Size Bike for My Child? (Wheel Size by Age)
Kids bikes are sold by wheel size, not frame size - and getting the size right matters far more than the brand. Here’s how to find the right fit.
Ready to choose?
We compared 10 kids bikes on ride quality, weight, build and value - balance bikes, first pedal bikes and geared bikes, for every age and budget.
The quick wheel-size chart
Use age as a starting point, but height (inseam) is more accurate. When between sizes, size down for a nervous beginner and up for a confident rider.
| Wheel size | Typical age | Approx. height | What it’s for |
|---|---|---|---|
| 12″ | 2–4 yrs | 85–100 cm | Balance bike or first pedal bike |
| 14″ | 3–5 yrs | 95–110 cm | First pedal bike, often with training wheels |
| 16″ | 4–7 yrs | 105–120 cm | Confident first pedal bike, hand brakes |
| 20″ | 6–9 yrs | 120–135 cm | First geared bikes appear |
| 24″ | 8–11 yrs | 135–150 cm | Geared bikes; last size before adult small |
| 26″ | 10+ yrs | 150 cm+ | Small adult bikes / older kids |
How to check the fit properly
The chart gets you close, but a real fit check is better. Sit your child on the saddle with hands on the bars:
- First bike / nervous rider: both feet should sit flat on the ground.
- Confident rider: the balls of the feet should reach the ground.
- They should be able to reach and squeeze the brakes comfortably.
Always measure your child’s inseam and check the specific manufacturer’s size chart - sizing varies between brands.
Why size matters more than brand
A bike that’s too big is genuinely dangerous - a child can’t control it, stop safely or put their feet down. Too small and they’ll outgrow it in months and be cramped. Get the size right first, then choose the lightest, best-value bike in that size.
Don’t buy too big “to grow into”
It’s tempting to size up to make a bike last, but a too-big bike knocks a child’s confidence and can cause falls. Buy the right size now; kids bikes (especially premium ones) hold resale value well when you move up.
Ready to choose?
We compared 10 kids bikes on ride quality, weight, build and value - balance bikes, first pedal bikes and geared bikes, for every age and budget.