The kids' bike sizing guide below will give you an overview of the various kids bike sizes, and show you how to choose the right size bike for your child based on leg length and rider experience rather than the ineffective method of age and wheel size.
What, how can this be? This is because the same size bike can have very different geometries, especially when you find brands like Guardian Bikes that design bikes specifically for kids.
When purchasing a kids bike, you should never choose a bike size based on an age range that is listed on a sizing chart. There are 2 main reasons for this:
Bike sizing is the most important aspect to get right when deciding on a bike for your child. If the bike is too big or too small, it can ruin your child's biking experience and lead to accidents.
Kids bikes come in these different sizes which are based on the wheel size of the bike: 12 inch, 14 inch, 16 inch, 18 inch, 20 inch, 24 inch, and now even 26 inch. The wheel size is based on the diameter of the tire (see below) and as each tire size gets larger, so does the size of the bicycle frame. These different wheel and frame sizes help companies design bicycles that will fit kids of all ages. The most common sizes are: 12 inch, 14 inch, 16 inch, 20 inch, and 24 inch. You will learn later on why wheel size is NOT the best way to choose a bicycle for your child.
If you have ever purchased a bike before, you have probably seen a chart like the one below. These charts are designed for you to use your child's height to determine the correct wheel size. Sounds simple right? Then you finally get into the store, sit your child on a few bikes with the correct wheel size, only to realize that the bikes seem to fit differently.
The main problem is the size of the bike is not solely determined by the wheel size of the bike. The size of the frame and design of the geometry also matter. This is why the same company can have two 20 inches bikes that are designed to fit children of completely different heights. An example of this is illustrated below when comparing Guardian’s 20 inch small vs 20 inch large kids bike sizes.
Figure 1: 20 Inch Small Bike
Figure 2: 20 Inch Large Bike
Figure 1: 20 Inch Small Bike
Figure 2: 20 Inch Large Bike
Notice how both bikes have 20 inch wheels but the bike in figure 1 has a shorter wheelbase and lower seat position. This bike has been specifically designed for a smaller kid. There are more extreme examples if you begin to compare two bikes from different brands where the minimum seat height of two bikes with the same wheel size can vary up to 5 inches!
Another issue with this method is the difficulty in trying to figure out which bike is going to last the longest and how long the bike is going to last.
The most accurate way to find the right kids bike size for your child is to look at their bike leg length measurement and experience and compare it with the seat height of the bike. To make this easier, lets define each of these terms.
Bike Leg Length = measured from the top of the crotch to where your child’s feet touch the ground (with shoes on!).
Note - bike leg length is different than pant leg length.
Rider Experience = some questions include: have they ridden a bike before? Did they start on a balance bike? Are they timid or confident?
Seat height = this is the range of how low and how high the seat will go on a bike. For example, our Guardian 16 inch bike has a seat height range of 18.5 – 23.5 in
Here is an easy step-by-step guide for measuring your child’s leg length:
1
Have them stand up straight against a wall with their feet shoulder width apart and their shoes on.
2
If you want to ensure your measurement is as accurate as possible, you can place a book (hardbound) between their legs and to the top of the crotch area.
3
Measure from the ground to the top of the book (to their crotch) to get their bike leg length.
Now that you have measured their leg length, the next step is to understand their riding experience.
If your child is under the age of 4 and has not ridden a balance bike or pedal bike before, we strongly recommend you take a look at starting them off on a balance bike. You can learn more about balance bikes at the bottom of this page.
This will be my child’s first pedal bike & did NOT use a balance bike Created with Lunacy Created with Lunacy
If this is your child’s first pedal bike and they didn’t use a balance bike, then their feet should be flat on the ground when sitting on the seat. By teaching your child to balance first rather than with trainining wheels, your child will learn much faster and be riding on their own before you know it.
This will be my child’s first pedal bike & did use a balance bike Created with Lunacy Created with Lunacy
Timid Riders
If this is your child’s first pedal bike and they used a balance bike, then their feet should be flat on the ground when sitting on the seat.
Confident Riders
If this is your child’s first pedal bike and they used a balance bike, then their heels can be up to 2 inches off the ground when sitting on the seat.
This will be my child’s second (+) pedal bike Created with Lunacy Created with Lunacy
If your child has already ridden a bike without training wheels, then they should be riding with their heels 2-3 inches off the ground while sitting on the seat. This is great news for you as a parent because your child will get more life out of the bike than kids who currently have less experience. With their heels 2-3 inches off the ground and the seat set higher, your child will have proper leg extension for maximum pedaling efficiency.
Now that you have measured their leg length and looked at their experience, the final step is to match that up against the seat height of a bike.
As parents, we like to purchase things (or items) for our kids that will last. When it comes to a kids bike, you will always want to get your kid on a bike towards the minimum seat height so that the bike has room to grow.
Minimum seat height = Inseam + heels off the ground (see above on experience)
I.E. a new rider with an leg length of 18 inches
Now that you know their minimum seat height, you can start shopping around!
Want to make it easy on yourself? Use our RideSizer® tool below. Please note this only works for Guardian Kids Bikes.
When choosing the perfect kid’s bike, one important factor to consider is the size. And if you’ve been contemplating what age is suitable for a 20-inch bike, you’ve come to the right place.
In this guide, we will explore the ins and outs of this particular size. Let’s get started!
When choosing the right bike size for your child, understanding how it is determined is key. Bike sizes are often based on the diameter of the wheels, measured in inches. One common size that parents often consider is the 20-inch bike.
Measuring your child’s inseam length is an essential step. The inseam length refers to the distance from the crotch to the ground. This measurement helps ensure that your child can do the following:
comfortably straddle the bike with their feet flat on the ground
maintain a slight bend in the knees
A proper inseam measurement, overall, allows for optimal balance and control while riding.
Next is the wheel size of a bike. In the case of 20-inch bikes, the measurement refers to the diameter of the wheels. A 20-inch wheel size is often considered an intermediate size. A suitable one for children who have outgrown smaller bikes but are not yet ready for larger ones.
The larger wheels provide more stability and control compared to smaller sizes. This makes it excellent for kids who have developed better coordination and balance.
A 20-inch bike refers to the size of the wheels on the bicycle. The measurement of 20 inches corresponds to the diameter of the wheels. This wheel size is commonly used for kids’ bikes and is known for its versatility and suitability.
As mentioned, 20-inch bikes are often considered an intermediate size. They bridge the gap between smaller sizes designed for younger children and larger sizes meant for older kids or adults.
Besides the wheel size, 20-inch bikes come in various frame designs and configurations. This includes different types of brakes, gears, and suspension options. These features can vary depending on the intended use of the bike. For instance, for casual neighbourhood rides, off-road adventures, or BMX-style tricks.
It’s important to consider your child's specific needs when choosing one to ensure a suitable match. Below are the key features and characteristics that make a 20-inch bike stand out:
Typically made of lightweight materials like aluminium or steel. The frame design can vary, depending on the intended use of the bike.
Provides a good balance of stability and agility. Suitable for various terrains and riding styles.
The most common types are coaster brakes, activated by pedalling backwards. Another is the hand brakes, which are located on the handlebars.
Some models offer multiple gears to provide versatility in different riding conditions.
Suspension forks absorb shocks and provide a smoother ride, reducing bump impacts.
This includes seat height and handlebar height. This adjustability allows parents to fine-tune the bike’s fit as their child grows.
The specific features of a 20-inch bike can vary between different brands and models. Consider your child’s riding preferences, the bike’s intended use, and safety requirements.
The typical age range for 20-inch bikes is generally considered to be between 6 and 9 years old. But it can vary depending on a child’s height, leg length, and individual development.
Children grow at different rates and their height and leg length. This can significantly impact their ability to ride a 20-inch bike comfortably. Some may reach the height and leg length required for a 20-inch bike earlier or later than others of the same age.
Generally, most 6-year-olds will be able to ride one if they have an average height and leg length for their age. Children who are taller or have longer legs may be able to transition to a 20-inch bike earlier. Meanwhile, shorter ones may need to continue riding smaller bikes beyond the age of 9.
Consider both age and physical attributes to see if a 20-inch bike is suitable for your child. Take into account their height, leg length, and riding abilities. Doing so will help you make an informed decision and provide them with the best bicycle.
When determining if a child is ready for a 20-inch bike, several key factors should be considered. These factors help assess a child’s physical abilities and readiness:
Ensure your child has developed adequate stability. They should maintain their balance while pedalling, turning, and stopping.
Are they able to ride smoothly and steer confidently? Can they control their speed?
: Have they mastered starting, stopping, and turning? Are they able to ride independently without relying heavily on
stabilisers
?
Evaluate if your child has the necessary strength to pedal comfortably. Plus, see that they can handle the bike’s increased weight and size.
Ensure that your child can follow basic safety rules. Pay attention to their surroundings and make responsible decisions while riding.
These factors may vary depending on each child’s individual development. Some children may be ready for a 20-inch bike at a younger age. Other kids may need more time to develop the necessary skills and physical abilities.
Weigh up your child’s readiness. Consider their traits and abilities before making the transition to this bike size.
Every child is unique, and their growth patterns may differ. By ensuring a proper fit and considering wheel size, you can provide your child with the best 20-inch wheel bike. A two-wheel that promotes confidence, comfort, and a joyous riding experience.