A Common Sense Guide to Bicycles

How to Measure a Kids Bike

This tool shows how to measure a kids bike so you can see the appropriate age and height range for the bike.


Wheel Size (D) - This is the outer diameter of the wheel, with the tire installed on the rim.

Kids Bike Sizing (in) - Kids bikes are measured in inches.

Kids bikes without pedals are called run bikes and have wheels that measure from 8" to 12".

Rider Charts

Select a kids bike size to see a chart of suitable riders by age and height.

Frame Diagram

Kids bike frame with wheel measurement highlighted

Measuring Instructions

  1. Measure the diameter of the existing tire, as illustrated above (D), or look on the tire for the size (it looks like this: nn" x n.n").
  2. If you find the tire size, the first dimension is the tire diameter, the second dimension is the tire thickness.
  3. Record the tire diameter, as this also represents the bike frame size.
  4. Select your bike size from the drop-down on the right to see a rider chart.