Which bike frame size do I need?

Are you looking for a new bike and unsure about the right size and which frame size you need for your height? In this article, we help you determine the correct frame size and saddle height.

What is the definition of frame size?

The frame size, or frame height, is the distance from the bottom bracket to the point on the frame where the seat post comes out, usually expressed in centimetres.

The frame size is equal to the length of the seat tube. This is the distance between the centre of the bottom bracket and the top of the seat tube. Women’s bikes usually range from size 51 to 61 cm. For men’s bikes this is 54 to 66 cm. Frames are also often indicated as S, M, L and XL.

How do I determine the right frame size?

You can determine your frame size based on your inseam length or based on your overall body height.

Determining frame size based on your inseam length:

Measure the length of your inseam with bare feet (place them about 15 cm apart). This means from the floor up to your crotch. At the bike shop they have a special measuring device. See also the table (at the end of this page) for an estimate of this inseam length. Multiply your inseam length by 0.68. Round the result down. That’s your correct frame size.

Example calculation

90 cm x 0.68 = 61.2 cm. Rounded: 61 cm.

Determining frame size based on your body height:

The table is useful for both men’s city bikes and women’s city bikes.

Below you’ll find an indication of frame size based on body height. 

Both are rough ways of calculating frame size; depending on your body proportions (for example, longer legs than average), it’s wise to ask for personalised advice at a bike shop. The type of saddle can also influence the required frame size. For example, a suspension seat post already raises the bike by about 3 to 4 centimetres.

The type of bike can also determine the frame size you need. The so‑called frame geometry affects your posture and riding position (upright, slightly leaned forward, or very sporty). And what is your ideal riding position to prevent complaints in shoulders, wrists, back, neck and knees? For this as well, it can be helpful to visit a bike shop near you. We’ve put body height and frame size together in a handy table.

How do I determine the frame size for a kids’ bike?

Up to the start of puberty, you’ll probably buy four to five bikes for your child. How quickly your child grows determines how soon you’ll need a larger kids’ bike. Often you’ll look for a new kids’ bike based on the wheel size in inches. The inch size tells you something about the tyre size rather than the frame height. Of course, wheel size is an important factor in determining the right size bike for your child. But frame size is also important in choosing the right bike size for your child. So how exactly do you determine the right kids’ bike size?

A good guideline is your child’s clothing size. The height from the bike saddle to the ground (inseam length) also gives a good indication of the bike size, as described above. The saddle should be in its lowest position so it can still be raised as the child grows. There is no difference in size between a girls’ bike and a boys’ bike. With kids’ bikes, size is indicated in inches. This is actually the size of the tyre.

Online bike shops with filtering by frame size or body height

There are of course many bike shops in the Netherlands, both physical and online. To make things easier for you, we’ve put together a list of the best online bike shops:

adobike.nl

internet-bikes.com

giga-bikes.nl

fietsenwinkeldiscounter.nl

speedpedelecs.com

gazelle.nl

Where can I buy the best bikes?

It’s becoming harder to quickly and easily find the right bike shop. Online, the range is enormous, but not every bike shop is equally good and reliable. To help you figure out where you can best order a bike online, we’ve written the article “Top 10 online bike shops”.