Bicycle frame size is a parameter that affects the length and height of the frame, i.e. its overall size. As the size of the frame increases or decreases, the upper, lower, and seat tube changes proportionally.

According to this website, by choosing the right standover height of a bike, you will be able to ride it comfortably every day without back/knee pain. When you buy a bicycle for sports or competition, choosing the right frame size is crucial.

There are 3 types of signs: ” (inches), conventional units (XS, S, M, L, XL), and centimeters (cm). The size range of a particular bicycle model is usually either even or odd.

Choosing mountain, city, and hybrid bike sizes

Below is the most popular size chart suitable for choosing most bicycles. Size matches are based on extensive sales experience, as well as being compared with many size charts of bicycle manufacturers. 

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

13″-14.5″                     57.08-61.02 33-36                    XS (XSmall)

15″-16″                        62.2-67.71 38-40                     S (Small)

17″-18″                        66.14-71.65 43-47                     M (Meduim)

19″-20″                        70.07-74.8 48-52                     L (Large) 

21″-22″                        74-78.74 55-58                     XL (XLarge) 

23″-24″                        78.74-82.67 59-62                     XXL (Maximum)

  • Mountain bikes. When choosing hardtails, you can safely use this chart. There are rare exceptions such as Gary Fisher’s models that are longer in the base than most other bikes. Keep this in mind if you’re going to ride more than do sports. Dual frame suspensions are often only available in 2-3 sizes.
  • City bikes (comfortable models). If you’re in transition height, such as 70″ or 65″, note the presence of a suspension seatpost. It does not allow the saddle to be fully lowered into the frame, as it can be done on all mountain bikes. Therefore, with the height of 70″ it is better to take a bike with an 18″ frame than with 20″, and with the height of 65″ you will feel more comfortable on a 16″ frame than 18″. 
  • Cruisers. Keep it simple when deciding on a standover height of a cruiser – these models have only 1 or 2 of them. Cruisers are usually designed for an average woman (61-70″) and a man (67-75″). If you have any doubts, ask a salesman.
  • Hybrids. Here it’s the same thing as with comfortable city bikes (shock-absorbing seat pins).

Choosing city and road bikes sizes (including Giant Compact Road™)

When choosing a road bike, I suggest you use the chart taken from the original catalog of bicycles Giant 2011 – 2012. All road and city bikes are available with Compact Road geometry.

Frame size – Cyclist’s height – Frame size (Giant Compact Road) – Frame length (seat/top)

19.29-20.07 61.8-64.17 XS 16.53 / 20.47

20.07-21.26 64.17-66.9 S 17.32 / 21.06

21.65-22.44 66.9-70 M 19.68 / 21.85

22.44-23.22 70-72.04 M/L 21.06 / 22.44

22.83-23.62 72.04-74.8 L 21.85 / 23.03

24-24.8 74.8-77.95 XL 23.03 / 24.01

Choosing folding bike sizes (Author, Giant, Shulz, Strida, etc.)

Most folding bikes are available in one size designed for the average person height from 61” to 73”.

Bike model – Optimal height

Author Simplex – 59.05-76.77

Shulz Easy – 59.05-72.83

Shulz Goa-3 – 61.02-72.83

Giant Expressway 1 и 2 – 61.02-72.83

Giant Halfway – 63-70.87

Giant Subway – 63-70.86

Strida LT, 5.2, SX, SD – 60.23-75.98

Choosing children’s bike sizes

All children’s bicycles are divided according to age and height. There is now a great deal of confusion on the Internet between bike sizes and children’s age. Therefore, I have taken this issue seriously and came up with a detailed size chart.

Child’s age (y/o) – Height (inches) – Wheel diameter (inches)

      1 – 3         29.52 to 37.4       < 12″

      3 – 4         33.46 to 39.37         12″

      4 – 6         39.37 to 47.24         16″

      6 – 9         45.27 to 53.14         20″

      9 – 13                 51.18 to 61.02         24″

The height and size of bicycle wheels were not just made up out of nowhere. In preparing this chart, the classifications of kids bike manufacturers themselves have been studied, as well as height charts for kids from 1 to 15 y/o. If your child grows slower or faster than the average, you can buy a smaller or larger bicycle, respectively. There is nothing wrong with this.

Choosing BMX bike sizes

A standover height for these stunt bikes is the length of the upper frame tube (top tube, TT). Choosing BMX is very individual and subjective. Someone likes to ride on short frames, someone prefers long. To determine how convenient it will be exactly for you, it is best to take a ride on friends’ or acquaintances’ bike. In the case of Giant’s BMX, the situation is like this: cheaper models are equipped with frames with a smaller standover height (on the prospect of that teenagers are basically buying inexpensive models). In other cases, I suggest using the chart (the accuracy of the information is not guaranteed!).

Your height Frame size

55.12-59.05 19.5″

59.05-66.92 20.0″

66.93-70.86 20.5″

70.86-74.8 21.0″

General recommendations and FAQ

What else do you need to consider when choosing from two suitable size options?

  • Assumed style of riding. For active and extreme riding it is better to choose a smaller bike – a bigger reserve of centimeters above the frame will give you confidence, and the bicycle will be more vivid. For a quiet ride through the city and parks, you can opt for the perfect fit.
  • Body build. If you have a slim or average shape, choose a large bike size. If you quite a large person, it is better to take a smaller size – it will be easier to sit, get off, and ride. 
  • Useful adjustments. You can always change your position by adjusting the mtb saddle height and handlebar tilt (not available on all models). On mountain bikes, the stem is most often non-adjustable – a safety standard used on bikes designed for active riding. In this case, a longer / shorter / higher / lower stem can be purchased, which is an absolutely normal experience.


Question: I’m 5’7″. Which bike size should I take, 16″ or 18″?

Answer: Choose according to your physique and intended style of riding. In most cases, it is better to take 18″.

Question: What if I have short arms or legs?

Answer: Take a smaller size, as the bike will be slightly lower and shorter. If you have short hands, you need to buy the shortest possible stem for your bike. If your legs are short, then lower the saddle at a minimum.

Question: What to do if I have long arms or legs?

Answer: Go for a bigger size. If you have long arms, get a long handlebar stem. If it’s your legs – raise your seat higher.

Question: Why do some bikes have a large range of sizes (from XS to XL), while others have only 2 or 3 sizes?

Answer: A wide size range is usually available for sports bikes, e.g. mountain and road bikes. For a cyclist, it’s important to choose a suitable standover height. But urban bikes usually have 1-3 variants of frame size, designed for a typical person height. Usually, it goes like this: if your height is up to 65″, then it’s “S”; from 65″ to 70.8″ – M; over 71″ – L.