A Common Sense Guide to Bicycles

How to Measure a Freestyle BMX Bike

Freestyle BMX frames have thick tubing and heavy duty 20" tires designed to accommodate the weight of the rider when landing jumps and tricks. The frame size is determined using the top tube length. The instructions below explain how to measure a freestyle BMX bike.

Freestyle BMX bike

Freestyle BMX Bike

Rider Charts

Once you know your bike's frame size, select it from the drop-down to see how tall riders should be to use this bike.


Top Tube Length (TT) - This is the length of the top tube, measured from the center of the seat tube to center of the head tube.

US BMX (in) - BMX bikes are measured in inches.

Frame Diagram

Freestyle BMX frame with top tube measurement highlighted

Measuring Instructions

  1. Identify intersection of the top tube and seat tube.
  2. Identify the intersection of the top tube and head tube.
  3. Measure the distance between these two points (TT) - this is the length of the top tube.
  4. Record your measurement in both centimeters (cm) and inches (to the nearest half-inch).
  5. Select your bike size from the drop-down on the right to see a rider height chart.