How to Choose a Kids' Bike: Size, Control and Riding Confidence

How to Choose a Kids' Bike in 4 Steps

1. Measure your child. Find out their height and inside leg measurement.
2. Choose a suitable size. Use the general size chart to narrow your options down to one or two wheel sizes.
3. Compare specific models. Check the recommended rider height, saddle height adjustment range and saddle-to-pedal distance.
4. Check how well the bike fits. Watch how your child gets on, reaches the handlebars and brakes, and handles the bike overall. Beginners can try walking alongside it and making their first attempts, while more confident riders can also practise setting off, turning and stopping. Take their experience and physical ability into account.

What Size Kids' Bike Should You Choose for Your Child's Height?

Children's bike sizes are usually described by wheel diameter in inches: 12, 14, 16, 20, 24 or 26. But the same wheel size doesn't necessarily mean the bikes are the same size. Models can differ in standover height, frame length and the distance between the saddle and handlebars. And two children of the same height won't necessarily have the same leg length.

Use the chart below as a starting point only. The dimensions of the specific bike and how well it fits your child should always guide your final choice.

This chart is intended as a general guide across different manufacturers. The height ranges deliberately overlap: there is no universal formula for converting a child's height into wheel size. For example, our Koolo 20 is designed for children 110–130 cm tall, while the general chart gives a wider range for 20-inch bikes.

Choosing by age. Age can be useful as a rough guide, but height, body proportions and your child's abilities matter more when buying a bike. Three-year-olds can vary greatly in both height and riding confidence.

What if your child falls between two sizes? Compare the actual models and take your child's experience and physical ability into account. We'll look at this in more detail below.

How to Measure Your Child for a Bike

Before you start comparing models, grab a tape measure and ask your child to stand still for a moment. You only need two measurements:

1. Your child's height. Ask them to stand straight against a wall without shoes and measure their height.
2. Inside leg measurement. Place a firm book between your child's legs and gently raise it as though they were sitting on a saddle. Measure from the top edge of the book to the floor.

Write both measurements down. Compare your child's height with the recommended range for the model you're considering. Their inside leg measurement will help you assess whether the riding position and reach to the pedals can be adjusted correctly.

That's why, for Yedoo bikes, we also provide the minimum and maximum saddle-to-pedal distance, measured with the pedal at its lowest point. This measurement is related to your child's inside leg measurement, but it isn't the same thing. Foot position on the pedal and a slight bend in the knee also matter when pedalling.

How Can You Tell If a Bike Really Fits Your Child? Five Simple Checks

The numbers in a size chart help you shortlist suitable bikes. What really matters is how your child feels on them and what they can manage. Beginners don't need to pedal off perfectly for you to assess the fit – there's plenty you can check beforehand.

1. Getting on and off. Your child should be able to stand comfortably over the frame and swing a leg over without struggling to keep their balance. There should be enough clearance around the crotch when they stand over the bike.
2. Reaching the ground when stopping. Beginners should be able to reach the ground with both feet while sitting on the saddle, at least with their toes. For their very first attempts, setting the saddle a little lower can help them feel more secure when stopping. More experienced riders can use a higher saddle for more efficient pedalling. What matters is that your child can stop safely, put a foot down and get off the bike.
3. Reaching the handlebars. Your child should sit naturally, without having to fully stretch their arms or shift their whole body forwards when turning. Steering should feel secure, not strenuous.
4. Brakes within easy reach. Your child should be able to reach and squeeze the brake levers without overstretching their fingers. If the lever reach is adjustable, have it set to suit their hands. After all, even the best brakes are no help if a young rider can't operate them.
5. Handling the bike and making the first attempts. It doesn't matter if your child can't ride yet. Let them walk alongside the bike, get on and off, and try the brakes. Watch whether they can handle it naturally. More experienced riders can also practise setting off, turning and stopping in a safe, traffic-free place under adult supervision.

A bike may be too big if your child has to stretch to reach the handlebars, struggles to put their feet down when stopping or feels nervous every time they get off.

A bike may be too small if, even after it has been adjusted correctly, your child's knees rise too high when pedalling, they feel cramped and there's not enough room for a natural riding position.

What if Your Child Is Between Two Bike Sizes?

Your child's height may fall within the recommended range for two bike sizes, but that doesn't necessarily mean both bikes will fit. Start by checking the dimensions of each model, your child's riding position and whether they can control the bike safely. Only if both sizes fit should you also consider your child's experience, coordination and physical ability.

Beginners will usually feel more comfortable on a smaller bike, which is generally lighter and easier to handle. It can help them manoeuvre the bike more easily and feel more confident when stopping. A more experienced and physically capable child may also manage a larger size, provided it fits properly. But don't choose a bigger bike simply so it will last longer.

Choosing Between 14″ and 16″ Bikes?

Pay particular attention to standover height, the saddle height adjustment range, reach to the handlebars and brake levers, and how easily your child can handle the bike. For a complete beginner, the smaller Koolo 14 may be easier to control.

However, if your child can already balance confidently on a balance bike, has good coordination and fits the Koolo 16 properly, there's no need to start with the smaller size just for the sake of it.

Choosing Between 16″ and 20″ Bikes?

The differences here may go beyond size to include the bike's components and features. For example, the Yedoo Koolo 16 has a simple single-speed drivetrain, while the Koolo 20 offers seven-speed gearing.

For beginners, the simplicity of the 16″ model can be an advantage, allowing them to focus on riding rather than changing gears. More experienced riders can benefit from shifting gears on longer, hillier rides. But what matters is whether your child can control the larger bike confidently.

And Between 20″ and 24″ Bikes?

The same principle applies. Don't base your decision on age alone, or on the fact that your child is approaching the upper end of the recommended height range. Compare frame dimensions, reach to the controls and how confidently your child can manoeuvre each bike. If both sizes fit, also consider your child's experience and where and how long they'll be riding.

When Is Your Child Ready to Move from a Balance Bike to Their First Pedal Bike?

Age alone doesn't determine when a child is ready to move on to a pedal bike. A better sign is that they can balance, steer, slow down or stop on a balance bike – and, most importantly, want to try pedalling. Some children are ready sooner, while others are happy to keep riding their balance bikes for a while longer. Both are perfectly fine.

Your child will already have practised balancing, steering and spatial awareness on their balance bike. On a pedal bike, they'll also need to learn to pedal and coordinate several actions. Braking may work differently, too: some balance bikes have no hand-operated brake, while others – including Yedoo balance bikes – have a rear brake. On a bike with two hand-operated brakes, children learn to operate the front and rear brakes separately before gradually learning to use them together.

Give your child a flat, traffic-free area, let them practise in short bursts and allow them to stop before the fun turns into a chore. Even ten metres can be a great start.

Do Children Need Stabilisers to Learn to Ride?

Not necessarily. A balance bike teaches children to actively maintain their balance as the bike leans, whereas stabilisers limit how far it can lean. Research suggests that children who start on balance bikes often learn to ride independently sooner than those who practise with stabilisers. That doesn't mean using stabilisers is always a bad idea; for some children, they may be part of an individual approach to learning.

If your child can already balance confidently, it's worth trying the move to a pedal bike without stabilisers first. When developing our Koolo bikes, we chose a different design rather than making it possible to fit stabilisers. As a result, stabilisers cannot be fitted to Koolo bikes.

What If Your Child Has Outgrown Their Balance Bike but Isn't Ready for a Pedal Bike Yet?

There's no need to rush the transition. Larger balance bikes are also available for older children. For example, the Yedoo TooToo XL has 14″ wheels and is designed for children approximately 95 cm tall and up. Your child can keep developing their balance skills and move on to pedalling when they feel ready.

Already Have a Yedoo Balance Bike and Thinking of Buying a Pedal Bike?

Return your balance bike to us and, when you buy any Yedoo Koolo children's bike, we'll deduct the full amount you paid for the balance bike. Simply provide proof of purchase. Find out how our Time to Pedal trade-in programme works.

How Important Is the Weight of a Kids' Bike?

For a young rider, a bike can weigh a substantial proportion of their own body weight. What an adult can easily lift with one hand may be a real challenge for a child. A lighter bike is easier to set off on, manoeuvre and pick up off the ground.

But the lightest bike isn't necessarily the best. It also matters where those grams have been saved. Reducing weight shouldn't come at the expense of the strength, functionality or lifespan of the components.

Plastic parts have their place on a bike, but for some components that come under greater stress, durable metal parts may be a better choice. So when comparing bikes, look beyond weight and consider the quality of the components, how well they work and how easy they are to maintain.

That's the approach we take at Yedoo. We design lightweight children's bikes without compromising on functionality, durability or longevity. We're not focused on shaving off every last gram, but on creating bikes that children can handle easily and that are built to last.

What Brakes Should You Choose for a Kids' Bike?

Children's bikes come with several different types of braking systems. What matters most is whether your child can apply the brakes promptly, smoothly and reliably. The systems differ not only in braking performance but also in how they're operated.

Coaster Brakes (Back-Pedal Brakes)

Your child brakes by pushing backwards on the pedals. The brake acts on the rear wheel and is usually built into the hub.

The advantage is simple operation without a hand-operated rear brake lever. Possible drawbacks include braking being dependent on the position of the cranks and the inability to rotate the pedals backwards freely to get them into a suitable position before setting off. So a coaster brake isn't necessarily a bad choice, but it does have its limitations.

V-Brakes (Rim Brakes)

These are operated using brake levers on the handlebars, which press brake blocks against the wheel rim. When correctly adjusted and fitted with levers designed for small hands, they provide effective braking with good control over braking force.

Their advantages also include a relatively simple design, low weight and easy maintenance.

Disc Brakes

These work by pressing brake pads against a disc rotor near the wheel hub. They can be mechanical or hydraulic.

Their advantages become particularly noticeable in more demanding conditions, such as frequent riding in mud or wet weather, or on longer descents. Depending on the specific design, however, they may add weight, be more complex and require more involved servicing.

How to Choose?

Above all, check whether your child can operate the brakes using their own strength, reach the brake levers comfortably, and slow down and stop smoothly. On a bike with two hand-operated brakes, it's important to teach your child to use both the front and rear brakes with care and control.

For everyday children's cycling on cycle paths, surfaced trails and family outings, properly adjusted V-brakes are perfectly adequate.

That's why we've chosen them for Yedoo Koolo children's bikes, too. They provide effective braking while keeping weight low, the design simple and maintenance straightforward. Our bikes are primarily designed for everyday riding, where these qualities make sense.

Where Will Your Child Ride? Choosing a Bike for Different Surfaces

When choosing a children's bike, think about where your child will ride most often. Cycle paths, park paths, tarmac, gravel or firm forest tracks? For everyday riding, a versatile kids' bike with all-round tyres that can handle a variety of surfaces is a good choice.

But if you regularly take your child on more technically demanding trails, rocky tracks, steep descents through woodland or muddy routes, it makes sense to choose a bike designed specifically for those conditions. Suitable tyre tread, frame geometry and other features adapted to more challenging terrain all play an important role.

How Can You Tell When Your Child Has Outgrown Their Bike?

Children grow quickly, and a bike that fitted them perfectly not long ago may suddenly be too small. Before buying a larger bike, check whether there's still room to raise the saddle and, if adjustable, the handlebars. If your child is still hunched over after making these adjustments, their knees come up too high when pedalling, or they can't maintain a natural riding position, it's time to try the next size up. Never extend the seatpost or handlebar stem beyond their marked safety limits.

How to Choose a Kids' Bike Online When Your Child Can't Try It First

When choosing a particular model, check the recommended rider height, saddle height adjustment range, saddle-to-pedal distance and handlebar adjustment options.

If you're unsure which size to choose or your child falls between two sizes, we're happy to help. Email us at info@yedoo.eu or call us on +420 737 279 592. Have your child's height and inside leg measurement ready, along with an idea of whether they're just learning to ride or already ride confidently.

And don't forget a properly fitting cycle helmet.

If you find that the bike isn't quite the right fit for your child after delivery, you can return it within 14 days of receiving it. For more information, see our Returns and Warranty Claims page.

We also offer a full three-year warranty on Yedoo bikes. When you buy from our online shop, you'll receive an extended five-year warranty on the frame.

What Sizes Are Available in the Yedoo Koolo Kids' Bike Range?

When designing our Koolo children's bikes, we focused on low weight, easy handling and ergonomics tailored to children. To make comparing the models easier, we've put together an overview of their key dimensions.

And what about older children? We're also working on the Koolo 24, which will expand our children's bike range in 2027. We'll share more details soon.

Frequently Asked Questions from Parents

How Do You Choose Your Child's First Bike?

Above all, choose a bike that fits your child properly and is easy for them to handle. Their physical skills, experience with a balance bike and eagerness to start pedalling are all important.

How Do You Choose the Right Size Kids' Bike?

Start with your child's height and inside leg measurement. Use the size chart to find a suitable size, then check that the bike really fits your child and that they can control it safely.

Is the Lightest Kids' Bike Always the Best?

No. A lighter bike is easier to handle, but effective brakes, quality components and the bike's durability are just as important.

Does a Child Need Stabilisers to Learn to Ride a Bike?

No, they're not essential. A balance bike helps children develop their balance, while stabilisers limit how far the bike can lean. That's why, when developing our Koolo bikes, we chose a different design rather than making it possible to fit stabilisers. As a result, stabilisers cannot be fitted to Koolo bikes.

More Inspiration from Yedoo

Curious about how our Koolo children's bikes came to life? Or looking for tips on how to motivate children and make physical activity a natural part of their lives beyond organised clubs? Explore more articles on Yedoo Edu.

And if it's time to swap your child's balance bike for a pedal bike, take a look at our Time to Pedal trade-in programme.