How to Measure a Kids Bike Frame

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

Frame Diagram


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.


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.

8" to 12" Run Bike

12" Kids Bike

16" Kids Bike

20" Kids Bike

24" Kids Bike