How to choose a bike for a child

Are you contemplating what kind of a bike to choose for your child and what to focus on during selection? We'll try to help and advise you.

Choosing a children's bike brings joy, but also a bit of worry. After all, everything is a bit specific when it comes to children. We want the bike not to be too big, but also not too small after a short while. We don't know for sure if they'll even enjoy riding.

Moreover, today's options are boundless, which on one hand helps to perfectly tailor the choice, but on the other hand complicates it, if you're not well-versed in the selection or don't know exactly what features you need. And this article should help you with the basic selection.

Key links:

• children's bikes and balance bikes in our MTBIKER e-shop offer,
• children's helmets, protectors, gloves and other accessories for safe riding,
• lights and bells.

💡 Tip: The most important parameter is not the child's height, but their inseam length. While overall height is indicative, the length of the leg from the crotch to the ground (the so-called inseam) determines whether the child can safely reach the ground and whether the frame geometry allows for a natural riding position. When choosing sportier models today, we also pay close attention to low weight – an ideal children's bike should not weigh more than 35–40% of the child's weight.

We'll break everything down in more detail below.

The right size is key

Let's start with the basics. The most important thing when it comes to children's bikes is choosing the right size. Not so much the frame itself, but the wheels, which essentially form the starting point.

Of course, there's always a certain range. If we look closer, the boundary values often overlap. We'll get to that later; the chart will serve as an initial guide to help you narrow down your selection.


Age is, of course, approximate; every child is different. Therefore, it's good to look at body height, and the distance from the crotch to the ground (often referred to as “inseam”) is also a key piece of information.

The child should wear their shoes before the measurement. Then, you can use something sturdy and straight, for example a book, and align it against a wall atop their head. This will help you verify if the child can even reach the ground while on the bike – especially important for the youngest ones.

Once your selection is narrowed down, the best helper is the opportunity to try out the bike. Simply put, the child must feel comfortable and safe on it.

A good indicator of the correct size is that when standing astride the bike, a fist can fit between the top tube and the child's crotch. If you're buying a bike online, it's ideal to measure the child and aim for somewhere in the middle of the recommended range. This is precisely why the recommended sizes “overlap,” so you don't end up right on the edge between two sizes (see chart above).

What about a slightly larger bike?

You might be thinking now that it would be better to buy a slightly larger bike for the child to grow into. In the past, this was a very common practice, mainly because there wasn't much choice. However, this strategy carries a risk – the child might not enjoy the bike for a long time.

If the bike is too big, it will be difficult to control, which significantly reduces riding safety. Therefore, it's good to choose a bike that fits. Nowadays, the advantage is that children's bikes can be sold quite easily, for example, on our MTBIKER marketplace. And they usually “fly off the shelves” quickly...

12-inch wheels and balance bikes

Let's start with the category for the very youngest. For them, two options are possible: a balance bike or the smallest pedal bike. If the child can't reach the pedals, or you're simply worried they can't handle riding yet, a balance bike is the ideal solution. It could be said that a balance bike will be the ideal first “bike” for most young children. They can easily ride them even before turning two years old.

Children will most appreciate the simplicity of learning and good maneuverability.

Of course, it's crucial that they can already reach the ground, and today's balance bikes have adjustable seat and handlebar heights. This allows them to last for quite a long time, until children gain confidence or the desire to switch to a pedal bike. Or until they simply outgrow it...

Balance bikes are largely similar; in most cases, they have 12-inch wheels (you can find even smaller models for very tiny children). They differ in price, and very often you'll find interesting features on the more expensive ones. For example, a lightweight aluminium alloy frame, wider tires, or even footrests where the child can place their feet, or even a brake.


It's certainly not essential, as the child will primarily brake with their feet anyway, but it can help develop the habit. Moreover, today's balance bikes, such as the Kiru Race, can handle lighter terrain thanks to their wider tires, where an additional brake can come in handy.

With 12-inch pedal bikes, you'll often find removable training wheels. You can remove them from the bike or adjust their tilt to change the “support” during riding. These bikes are single-speed, meaning they have no gears and often brake by pedaling backward (coaster brake).


Children will most appreciate the simplicity of learning and good maneuverability. The bikes are equipped with a chain guard, so there's no risk of contact, and handlebar end protectors are also present. These come in handy in case of a fall, protecting hands, and also significantly reduce the chance of the handlebars slipping from the child's grasp.


Bikes allow for seat height adjustment, and very often handlebar height adjustment as well. This means they can easily adapt to a child's rapid growth.

14-inch bikes

If your child is a bit older or took to riding a balance bike “like a duck to water,” you can opt for a 14-inch version for their first pedal bike. They essentially have the exact same features and basic construction elements as 12-inch bikes, but very often you'll find them without training wheels.

The difference is also that bikes of this size very often no longer brake exclusively by pedaling backward, but may have a freewheel and a pair of independent brakes, like classic bikes.

16-inch bikes

It's very likely, that after a balance bike, a 16-inch version will be the first pedal bike – especially if the child still feels most comfortable on a balance bike, or if you buy their first bike at a later age (around 5-8 years old).

These are still excellent first bikes for learning, even for slightly older children; you'll find them with training wheels, with a coaster brake, but also with a freewheel and a pair of independent brakes for more advanced riders. What primarily decides is whether the child is a complete beginner or has ridden a bike before.

20-inch bikes

For children's bikes, low weight is a very important factor because it greatly influences the riding experience.

In this category, things start to get more interesting, as bikes begin to “specialize” more for specific requirements, and you'll find a wide range of models here. In this category, some models are already more focused on off-road riding, and you'll even find suspension forks on them. However, it's important to state right away that if your child doesn't yet have real ambitions and abilities to tackle more challenging terrain, simplicity and the lower weight of a classic rigid fork are still the better option.


Gears make a big difference in riding. Here, you already have the option to choose models with a derailleur. If your child has the desire and ambition to ride more, it's better to opt for a geared bike, which significantly expands its usability.

Conversely, if the child wants a bike more for fun and casual riding, feel free to choose a single-speed bike – subsequent maintenance is much simpler.


Brakes are an important element, and here you can already choose from 2 options. Once again, usage is the deciding factor; for casual riding, classic (rim) brakes are still more than sufficient, while ambitious “downhillers” will appreciate the power of disc brakes, or even hydraulic disc brakes.

Again, the trade-off for greater performance will be more demanding maintenance and also a slightly higher weight.

Low weight is important

Now we can pause for a moment and mention one important factor. And that is the reality that low weight greatly influences the riding experience. Children are smaller, and therefore feel every extra kilogram, not only when riding but also when handling the bike. More expensive models therefore focus precisely on reducing weight.

For an adult's bike, a 2 kg difference is almost negligible, but for a 20 kg child, it's a crucial factor. Imagine if you, as an 80 kg rider, had a bike that weighed 25 kg. This is how a child feels on a cheap, steel bike. Therefore, try to look for lightweight aluminium alloys (look for designations such as triple-butted aluminium).

Components are also important – often it's heavy steel handlebars or seat posts that add weight. Modern children's bikes (like models from premium brands) use duralumin components adapted to children's anatomy.

There's no need to necessarily choose suspension or the aforementioned hydraulic brakes if the goal is a bike for fun and casual riding. There's still time for those if the child doesn't have strong ambitions to ride in challenging terrain or doesn't explicitly demand those components. 🙂

24-inch bikes

It could be said that these bikes are already a kind of “miniature” of classic adult bikes, with the difference that the child has better maneuverability and adaptation to their stature.


They already form a kind of transitional stage, where the intended use plays a significant role. Does the child want to ride more off-road, jump on trails, or rather just ride around for fun? 🙂

If you don't want to invest in anything else, a helmet is still an absolute “must-have”.

Components are already adapted for specific use. If the child is more drawn to off-road riding than city streets, don't hesitate to adapt your choice accordingly, as the riding characteristics will be diametrically different. The child is already bigger and stronger, so a little extra weight for comfort and durability makes sense (especially suspension or disc brakes).


Conversely, if the child prefers faster riding around the neighborhood, they will unnecessarily “drag” a heavy bike and will much more appreciate lightness and sportier geometry. Especially if you want to go on longer trips together.

26 and 27.5-inch bikes

If your child is already too big for 24-inch models, it's good to opt for 26-inch bikes. What further distinguishes them from classic adult bicycles in this category are smaller frame sizes available (13 or 15.5 inches), as well as specifically adapted components – for example, a suspension fork tuned for a lighter rider's weight. The same selection criteria apply as we wrote for 24-inch models.


A specific category is 27.5-inch wheel bikes, whose greatest advantage is better off-road capability, meaning they handle roots and rocks better, and offer greater stability on descents.

When to choose a children's e-bike?

Just a few years ago, children's e-bikes were a rarity; today, they are a common part of global manufacturers' offer. However, they raise the question: won't children get lazy on them? Practical experience shows that the reality is the opposite. An e-bike often serves to bridge differences and allows families to spend more time together.

So, when should you consider an e-bike for a child? If you are active parents and your trips typically cover 40 km with an elevation gain of, say, around 800 metres, a child on a classic bike won't be able to keep up. An e-bike will allow everyone to enjoy the ride without you having to tow the child.

For a child who can't physically keep up, cycling can become a nightmare. The motor will help them overcome the toughest sections, so they return home with a smile and a sense of victory, not total exhaustion.

When choosing a children's e-bike, don't just look at the motor's power, but especially its performance characteristics:

• Weight: This is the biggest disadvantage. The battery and motor add kilograms (typically 15 – 18 kg). The child must be able to safely control the bike, especially when maneuvering in place or in case of a fall.
• Smooth power delivery: Cheap motors can “kick.” It's crucial for a child that the motor engages smoothly, otherwise, the bike might unexpectedly “shoot out” from under them on a technical climb.
• Speed limit: Most children's e-bikes have assistance limited to 20 km/h (instead of the standard 25 km/h). This is for safety, as children's reaction times are longer.
• Battery capacity: Children are light, so even with a smaller battery (e.g., 250 – 400 Wh), they can cover long distances. A smaller battery also keeps the overall weight of the bike lower.

An e-bike for a child is not a substitute for physical activity, but a tool to broaden horizons. If your child loves movement but you hold them back because they “can't go that far,” or conversely, they hold you back, an e-bike is a great solution.

However, if a child lacks basic technique on a classic bike, the motor won't compensate for it – riding technique should primarily be learned on a classic, lightweight bike.

Brake lever reach – small hands need a special approach

Many parents assume that if a bike is labeled “children's,” everything on it is automatically adapted for a child. This is often not the case – especially with brake levers. A child's hand is significantly shorter, and their fingers don't have the same strength as an adult's.

Why is reach adjustment so important? If a child has to “stretch” their fingers just to reach the lever tips, they lose a firm grip on the handlebars. This can lead to the handlebars slipping from their hand on rough terrain or during a sudden impact.

A finger can exert the most force when it is slightly bent at the joint. If the lever is too far, the child brakes only with their fingertips, which is simply not enough for a sudden stop.

How to adjust it correctly? Most modern children's bikes (whether with rim V-brakes or disc brakes) have a small adjustment screw on the inner side of the brake lever (usually for an Allen key). By tightening the screw, you move the lever closer to the handlebars (grip).

Ideal state: the child should have their fingers resting on the lever so that the first joint of their index and middle fingers comfortably wraps around the end of the lever, without having to release their grip from the handlebars.

For extremely small hands and when the lever is pulled very close to the handlebars, be careful that the lever doesn't hit the grip when fully squeezed before the bike stops. In such cases, the cable tension or hydraulic bleeding also needs to be adjusted.

💡 Our tip: If you're buying a bike for the youngest children, look for models labeled “Short Reach.” These levers are shorter and have an adjusted mechanical ratio, so even a weak child's squeeze will generate strong braking power. In premium models today, we also encounter hydraulic brakes, which are ideal for children – they require minimal force to operate.

Accessories that will definitely come in handy

It's important to say that buying the bike itself isn't the end of it. If you don't want to invest in anything else, a helmet is still an absolute “must-have.” It truly forms the basis of safety, and it doesn't matter if we're talking about balance bikes or bikes for older children.

Today, there's a selection for all categories, and there's nothing better than teaching a child to wear a helmet right from the very beginning. It will be ideal if you wear it everywhere too and lead by example. 😉


Very useful accessories include various lights, or reflective elements (bands, vests, Velcro, etc.). They don't cost much, but they significantly increase safety even during ordinary movement around a residential area. After all, scooters, cyclists, etc., often ride on paths, and a well-visible child is the least you can do for their passive safety.


And it's definitely worth mentioning protective gear like gloves or protectors. We definitely recommend gloves, especially because they prevent the child from scraping their palms, which are often “in the line of fire” during common falls. Today, there's a wide range of children's sizes and various colors to choose from, so everyone will find something.

You'll find a wide selection of models at the MTBIKER shop.