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Bike size and bike frame size calculator

The calculator will help you choose the size of the bike, bike frame, wheel size depending on the type of bike, your height, leg length or age.
If you are buying a new bike you must make sure that it fits perfectly to your proportions. You don't want to find out that it is inconvenient after buying a bicycle.
To prevent this, we have created a bicycle frame size calculator. Thanks to the calculator, you can check how to choose the size of the frame of a road bike, mountain bike, trekking bike or BMX bike. You will also learn how to choose a children's bike to suit your child's height or age.
If you're wondering what bike size you need or what is the ideal frame size for your height, these calculators will surely help.
As a result, in addition to frame sizes You will also learn which crank length to choose.

Bike size and bike frame size calculator

Road bike Road
Mountain bike Mountain
Trekking bike Trekking
BMX bike BMX
Kids bike Kids



leg length


Bike Size - Information

We determine the size of the bicycle frames by measuring the length of the section connecting the end of the seat tube with the center of the bottom bracket axis.
Bicycle manufacturers list frame sizes in three ways:
      - given in centimeters
      - in inches
      - given in the names S, M, L, XL

Measure the size of the bicycle frame

In order for the ride comfort to be appropriate, when determining the size of the bike, the size of the crank should also be selected. Please note that the crank acts as a lever. A longer crank will use less force, and a shorter one will allow you to pedal faster.
The length of the crank is measured from the center of the bottom bracket axle to the center of the pedal hole.
Measure the size of the bicycle frame

Road bikes , as the name suggests, are bikes that are built to maintain decent high speeds when riding on paved roads and asphalt.
A classic frame must consist of a main triangle of certain maximum and minimum sizes, a rear triangle and a front forks, the size and structure of which are strictly defined by the UCI organization.

Road bike frame sizes are given in centimeters regardless of style, however some manufacturers specify sizes in inches.
Frame measurement: The size of the frame is determined by measuring the length of the section connecting the end of the seat tube with the center of the bottom bracket axis.

Road bike

Mountain bikes or MTB are specially designed for off-road riding, e.g. mountain paths, forest trails, special obstacle courses. They have much in common with other types of bicycles, but their design focuses more on durability and performance when riding in more difficult conditions.
Bicycle frames come in various shapes depending on the purpose of the bicycle. The most common type of frame is a hardtail (frame without shock absorption), due to its simplicity of construction, low weight and low cost of production and service. In the case of bikes intended for more demanding descents, i.e. downhill and enduro bikes, frames with full suspension are used. Mountain bike frames are usually made of aluminum, less often steel, and frames made of carbon (carbon fiber) are becoming more and more popular. There are also titanium and bamboo frames.

Mountain bike frame sizes are usually in inches regardless of style.
Frame measurement: The frame size is determined by measuring the length of the section connecting the end of the seat tube with the center of the bottom bracket axis.

Mountain bike

Trekking (touring) bikes provide the comfort you need for long rides on paved surfaces and the stability you need to maintain fast speeds as you cycle your trail.
They combine the best features of road bikes and mountain bikes. They are used for advanced cycling tourism, consisting in traversing long, often multi-day routes, both on asphalt and unpaved roads.

Trekking bike frame sizes are usually given in inches.
Frame measurement: The frame size is determined by measuring the length of the section connecting the end of the seat tube with the center of the bottom bracket axis.

Trekking bike

BMX bikes owe their name to a type of sport that originated in the USA in the 1970s. BMX frames are made of various grades of steel and (mainly in the racing category) aluminum. Cheaper, low-end bikes are usually made of steel. High-end BMX bikes are mainly made of chrome steel or high-strength steel, although the latter is clearly heavier.
BMX bikes are available in the following models:
      Park - BMX (also called vert) bikes often lacking unnecessary weight, reducing structural excess in specific areas of the bike thanks to smooth transitions. They are designed to perform evolutions on specially built objects called skateparks.
      Dirt - BMX bikes are similar to park style BMX bikes, but have thicker tread tires for better grip on potentially loose surfaces. Used for show jumping on tracks specially designed for this purpose.
      Flatland - They have a slightly different geometry than traditional BMX bikes as riding on flat terrain requires a precise balance on many parts of the bike. They are used for evolutions performed on flat terrain, much like freestyle skateboarding in the past.
      Race - Racing type BMX bikes have a larger front sprocket than other BMX bikes to provide a high gear ratio, allowing you to pedal at high speed. BMX racing bikes must have brakes.
      Street - usually have metal studs attached to the axle to enable sliding down, for example, on railings. In addition, street BMX bikes tend to be heavier and stronger than traditional dirt or park BMX bikes due to the added stress encountered on hard, flat road surfaces. These bikes usually do not have brakes. This means that the rider uses his foot on the top of the rear tire to slow down. They are used for driving in the city, jumping on walls, handrails, etc.
Rower BMX

In the case of BMX bikes, the frame size is determined by measuring the length of the top tube, i.e. the length of the section from the center of the seat tube to the center of the head tube.
The position and size of the handlebars and the length of the stem are also important.
Measure the size of the BMX bike frame
BMX bike handlebar size measurement
Size of the BMX handlebar stem

Kids bikes equipped with durable frames and thick tires, designed especially for children. They are ideal for riding on flat, concrete or hard surfaces where the child can concentrate on riding the bike.
Kids bike

The size of the children's bicycle frame is determined in the same way as the frame size of other bicycles, ie by measuring the length of the section connecting the end of the seat tube with the center of the bottom bracket axle.
However, in the case of children's bicycles, the wheel size is more important than the frame size. Bicycles with different wheel sizes are often mounted on a frame of the same size.
Measuring the size of the children's bike frame

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