How Long Is A Bike? Why so many different sizes

bike length

Have you ever asked yourself how long a bike is? Have you wondered if it was big enough for you? Would it be better if it was slightly shorter? It's perfectly normal to wonder these things. I've wondered them all and then some. That's why I'm here to help you understand how long a bike is.

How Long Is A Bike?

A bike is as long as its wheelbase (from the center of the front wheel to the center of the rear wheel) and as tall as its top tube (from the bottom bracket to the seat collar). This length and height varies depending on the type of bike and its intended use (i.e., Mountain Bike vs. road bike).

You will find that the average adult bike is around 69" long. A kid's bike avearages out at about 18 to 28" long. These sizes are based on the inseam of a bike.

What Is A Bike's Inseam?

The inseam measurement is taken from the crotch down to the floor while standing straight up. If you're unsure of your child's inseam, there's an easy way to find it out. Take an old pair of pants and lay them flat on a table or the floor. Measure from the crotch down to where the hem touches the floor. This will give you an accurate inseam measurement. Now you can use our sizing chart below to determine what bike size your child needs.

Why Do Bikes Come In Different Sizes?

The most important reason for having different sizes is because people come in different shapes and sizes. The typical adult male ranges in height from 5 feet 4 inches to 6 feet 1 inch. Adult women are shorter, ranging between 5 feet to around 5 feet 8 inches.

Bikes come in all different sizes so that people of various heights can find one that is comfortable for them. Bike geometry (the design and shape) is also an important factor in determining size. The right size will allow you to ride with ease and maximize your pedaling efficiency.

What Size Should I Get For My Build And Height?

That depends on your preferred riding style and the terrain you'll be riding on. If you plan to ride mostly on easy trails or roads, a hardtail (bicycle with no rear suspension) might be all you need. If you want to go over more technical terrain and ride faster, then a full-suspension mountain bike will do better.

Basically, it boils down to personal preference. If you want a more responsive and maneuverable ride, then go with a smaller frame. If you want a smoother ride, then go with a larger frame.

Bike sizing chart

Age of rider Bike sizes (Height) Wheel Size
4-5 36" to 44" 14"
3-7 38" to 48" 16"
5-9 42" to 52" 18"
7+ 48" to 52" 20"
10+ 56" to 66" 22"
15+ 56" to 66" 26"


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Adult Road Bike Sizes

Height Of Adult Inseam Length Frame Size (Bike)
4'10" to 5'1" 25.5" to 27" 46 to 48 cm
5'0" 26.5 to 28" 48 to 50 cm
5'6" to 5'9"' 29.5" to 31" 52 to 54 cm
5'8" to 5'11" 30.5" to 32" 56 to 58 cm
5'10" to 6'1" 31.5t" to 33" 58 to 60 cm
6'0" to 6'3" 32.5" to 34" 60 to 62 cm
6'2" to 6'5" 34.5" to 36" 62 to 64 cm

A bike's length can be really important, but it isn't something you often hear about. This is a shame because a bike's size can play a huge role in how effective and comfortable the bike feels for you. You can get a very good fit on a bike through just altering its stem length, or even choosing a different sized frame with the same stem length. Many people don't know this, and they settle for an uncomfortable fit.

There are a lot of factors that affect the proper length of the bike. There's how tall you are, the style of riding and even your inseam. But really, don't stress too much about it. Unless you're buying an especially small bike (think kids), most bikes should be fine. Just make sure to test it out before you buy it.

Read more: How to decorate your bike

Looking for decals to decorate your bike? Browse's full line of custom die cut stickers to spruce up your bike frame. Give your road bike, mountain bike or motorcycle a custom look with custom holographic stickers. Don't forget to accessorize your bike accessories, including helmets and water bottles. Custom bike stickers and decals are made with waterproof laminate to resist scratches, rain, mud and sun exposure.

custom sticker

About Author:

image of Kevin Pommells

Hi, I'm Kevin Pommells, a lover of camping and the great outdoors as everyone says nowadays. I'm also a passionate soccer fan and the proud owner of, a website dedicated to helping campers and outdoor enthusiasts make the most of their adventures. With years of experience exploring the wilderness and a deep love for the sport of soccer, I'm always looking for new ways to combine my two passions and share my knowledge with others. Follow me for tips, tricks, and insights on all things camping and outdoor recreation.

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