If you’re wanting to get your child started with bike riding, or they’ve already started and needed an upgrade, you might be sitting here worried about what size of bike you need to get. It can be pretty confusing to get it right, but you probably already know that it’s super important.
If you get a bike that’s too small or too big then you’re child is going to have a much more difficult time keeping balanced as well as stopping safely.
How Are Children’s Bikes Sized?
Did you know that children’s bikes are measured and scaled differently from bikes for grown-ups? In fact, kids' bikes are sized by the sizer of their wheels rather than the size of their frame.
And then within the frame size, the standover height and seat-post heights can differ wildly, making it very difficult to find the exact size that is going to be comfortable and safe for your little cyclist.
The worst part is that if you’ve spent any time around multiple kids then you’ll know that they come in all different sizes as well, and it’s much more dependent on their development rather than their age.
Some 4-year-olds are absolutely tiny, whilst others already look like they’re 6. So, whilst a bike may be advertised for a 4-year-old, that doesn’t mean that it’s going to fit every 4-year-old.
Because of this, it’s a lot more sensible to buy a bike based on its measurements than the age group that it’s advertised for.
Measure Your Child
In order to make a good estimate as to what bike your kid is going to need and be most comfortable on, then you need to make sure you measure your child properly. You’ll need to measure their height and their inseam in order to make an accurate purchase.
If you’re buying this as a gift for a nephew or someone you may not have access to measure, then ask the child’s parent to measure them for you.
In order to make it easier when you come to finding the right bike, then you should measure in inches, as that’s the unit used to measure boke wheels. However, if you can’t, then you’ll just need to convert into inches once you’re done.
If you were wanting to keep the bike a secret, you might be worried about how you’re going to get the measurement or ask the child’s parents to get it without them getting suspicious.
So you could always say that you’re buying some nice clothes and what to make sure they’re going to fit. Lying is totally acceptable to keep awesome presents like bikes a secret.
Once you have the measurements, keep them handy for when you’ve finished the next step.
Look Up The Specs
You might have been able to use your intuition to guess that your child needs something like a 16” bike, but that doesn’t mean that every 16” bike is going to fit your kid perfectly.
As mentioned previously, different bikes have different standover heights or possible seat-post heights, and so it’s always going to be best to do a little more research to make sure that you find a bike that’s going to fit your little once as best as it can.
Now, it’s true that not every bike manufacturer is going to list the standover height for their bikes, which could be an issue, so if you’re wanting to be sure, you should try and find a manufacturer that does list this spec and then compare it to the kid’s inseam.
The standover height, in case you’re not sure, is the height of the top bar on the bike which is where your child is going to be positioned when standing with one leg over each side of the bike.
This means that your child’s inseam needs to be at least as tall as the standover height, ideally, there should be a little more space than that in order to let your child maneuver the bike more comfortably.
As well as the standover height, you also need to check the minimum and maximum height that the seat-post can be for any of the bikes that you’re considering.
What you need is going to be dependent on what kind of bike you’re buying - mainly whether you’re getting a balance bike or a pedal bike. For a balance bike, the height needs to be a little less than the inseam so that your kiddo can keep their feet flat on the ground.
For a pedal bike, however, you want to make sure that the minimum seat-post is about 1-3” higher than their inseam so that just their toes touch the ground, but not their whole feet.
If this is your child’s first pedal bike, then they won't be as confident cycling, and may still need to put their feet flat on the ground. In this case, you’d want to buy a bike where the minimum seat-post height is no more than 1” taller than your child’s inseam.
Find What Size Wheel They Need
The best to start narrowing down what your child needs is to just guess first, and go from there. That might sound counter-intuitive considering the specific measurements you needed in the previous two steps, but it’s just to get a good idea.
There are several charts you can find online that should help you narrow down your search depending on how tall or short your child is.
Their age should be a good indicator of what they’ll be ready for, but not all the time. Know your child’s height and measurements to ensure that you get the right-sized wheel.
What Size Bike For A 4-Year-Old
The average size of a 4-year-old is about 3’4” tall, in which case they would probably need a 14” wheel on their bike. If they’re particularly tall, for example above 3’7” then they might require a 16” wheel for their bike.
Some 4-year-olds won't be ready for a pedal bike yet and might benefit from still using or beginning to use a balance bike. However, if they’re more confident or comfortable balancing, then they might be ready for a proper pedal bike.
Keep their inseam and height in mind when looking for the perfect bike, but the only way you’re going to know for sure whether they fit on it properly is to go to an actual bike shop and test them out.