They used to think that all people are the same, so bikes should be the same as well. But then it turned out that all people are different, and bikes should be different. Or, at least, different sizes. In this article, bikesbros.com will talk about such an important part of a bicycle as its frame, as well as discuss the sizes and how to choose the right bike frame size according to a person’s height.

Let’s start with the fact that different manufacturers indicate bike frame sizes in different measurement units. It can be inches, centimeters or conditional units. Different tables compare all possible sizes with the height of a person so that you can easily choose the correct standover height of a bike for yourself. Check out the road bike size chart below.

Choosing the size of mountain bikes and city bikes

Frame size (inches) – Your height (inches) – Frame size (inches) – Frame size (c.u.)

13″ – 51-57 – 13 – XS 

14″ – 53-61 – 14 – XS

15″ – 57-63 – 15 – S

16″ – 59-65 – 16 – S

17″ – 61-67 – 17 – M

18″ – 65-70 – 18 – M

19″ – 67-71 – 19 – L

20″ – 70-73 – 20 – L

21″ – 71-75 – 21 – XL

22″ – 73-77 – 22 – XL

23″ – 75-79 – 23 – XXL

24″ – 77-83 – 24 – XXL

The only exception is folding bikes, as they are available in one size and designed for the average person with a height of 61 to 73 inches.

Choosing the size of city and road bikes

Frame size (inch) – Your height (inch) – Frame size (c.u.) – Frame length (seat/top)

19.29-20.07 – 61.8-64.17 – XS – 16.53/20.47

20.07-21.65 – 64.17-27.55 – S – 17.32/21.06

21.6-22.4 – 27.55-70.07 – M – 19.68/521.85

22.4-23.2 – 70.07-72.04 – M/L – 21.06/22.44

22.8-23.6 – 72.04-74.8 – L – 21.85/23.03

24.01-24.8 – 74.8-77.95 – XL – 23.03/24.01

When choosing a bike for training or competition, the exact frame size is essential because it directly affects the result.

Choosing the size of children’s bikes

Child’s age – Height (inches) – Wheel diameter (inches)

1-3 – 29.5 to 37.4 – < 12″

3-4 – 37.4 to 39.76 – 12″

4-6 – 39.76 to 45.27 – 16″

6-9 – 45.27 to 50.39 – 20”

9-13 – 50.39 to 61.02 – 24″

As for the size of a child or adolescent bike, the principles are slightly different here. Such bikes are chosen based on the wheel diameter.

What else is worth paying attention to when choosing the right frame size?

Style of riding. You probably noticed that there is always a few sizes, so with the same height, you can buy a bike of a different size. The choice here is more determined by the cyclist’s riding style, not just his/her height. For active and extreme riding, choosing from two options, it is better to opt for slightly smaller frame size since a larger stock of inches above the frame will give you confidence, and your bike will be more maneuverable. For quiet cruising around the city and parks, you can choose a slightly bigger frame. This is also appropriate for city bikes.

Body build and weight. Another factor influencing the frame size is the build of a cyclist. If you have a thin or ordinary build, you can buy a large bike. If you are big enough and have a considerable weight, it is better to take a smaller frame size – it will be more comfortable to sit down, easier to get off, and ride.

Additional adjustments. If a frame is a little out of size (or if your body is kind of unique), you can always adapt your position by adjusting the saddle height and handlebar stem inclination. Another trustworthy source worth taking a look at is bikesmarts.com.

How to measure the size of your bike frame by yourself?

The size of a bike frame is determined by the distance from the top of the seat tube to the center of the bottom bracket shell. Accordingly, when the seat tube size changes, all other bike sizes change proportionally. If you need to know the size of the bike frame in centimeters, you can convert this number at the rate of 1 inch = 2.54 cm.

Why is it important to choose the right size for your bike?

The right frame size not only affects your comfort, but also the safety of your riding. If you do not ride a bike of the correct size, you may get injured in an extreme situation, such as a sudden braking situation. Also, your shirt should too be too small, as you will have an improper seat which will result in too much pressure on the knee joints and may also lead to further physical injury.