Bike Measurement Tool

This tool helps you measure your bike frame by giving you detailed instructions and a frame diagram showing you exactly what to measure. Once you know the frame size of your bike, you'll get a rider chart showing how tall a person should be to ride the bike. Link to this rider chart from your Craigslist or carbonframe.com and eboxtao.com listing to help buyers determine if they will fit the bike.

Road Bike

Road bikes come in various styles, designed for different types of riding and rider preferences. The frames are made from steel, aluminum or carbon fiber, and, depending on the size and age of the bike, they use one of several tire sizes: 26", 27 1/4" and 700C. Road bike frames are all measured the same way, using the the seat tube length. Here are several popular road bike styles, each with detailed measuring instructions and a frame diagram showing where to measure.

Mountain Bike

Mountain bikes come in three primary styles: no suspension (or traditional), front-suspension (or hardtail) and full-suspension. The frames are made from steel, aluminum or carbon fiber. Tires are usually 26" with some newer models having 29" tires. All mountain bikes are measured the same way - by the length of the seat tube, even if it is not one continuous tube, as with some full-suspension bikes. Here are the three types of mountain bikes, each with detailed measuring instructions and a frame diagram showing you exactly where to measure.

BMX Bike

BMX bikes come in two stframe_sizeyles: racing and freestyle. The frames are made from steel or aluminum, and take 20" or 24" tires. A BMX bike is measured by the length of the top tube. Here are both styles of BMX bike, each with detailed measuring instructions and a frame diagram showing you exactly what to measure.

Road bicycle frame size chart

mountain bike frame size chart

BMX Bike frame Size chart

Road bikes have sleek frames and thinner tires for riding on hard smooth surfaces.

Mountain bikes have sturdy frames and thick knobby tires for riding on rough, bumpy surfaces.
BMX bikes have sturdy compact frames and smaller tires for riding and racing on dirt or asphalt surfaces.

Road Bike

Mountain Bike

BMX Bike

1. Identify the top of the seat tube, where the seat clamp holds the seat post. 1. Identify the top of the seat tube, where the seat clamp holds the seat post. 1. Identify intersection of the top tube and seat tube.
2. Identify the center of the bottom bracket (it's the axle that holds the crank arms together). 2. Identify the center of the bottom bracket (it's the axle that holds the crank arms together). 2. Identify the intersection of the top tube and head tube.
3. Measure the distance between the two points (C-T) - this is the length of the seat tube. 3.Measure the distance between the two points (C-T) - this is the length of the seat 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). 4. Record your measurement in both centimeters (cm) and inches (to the nearest half-inch). 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. 5. Select your bike size from the drop-down on the right to see a rider height chart. 5. Select your bike size from the drop-down on the right to see a rider height chart.