What Size Bike Do I Need? Bike Size Charts & Buying Tips

As a result of the COVID-19 pandemic, many have started riding bikes in a bid to improve or maintain their fitness levels. However, many often make the grave mistake of splurging on a new bike without assessing the bike fit to one’s body size.

When consumers get on an ill-fitting bike, they’ll experience discomfort, pain, and inefficiency as never before, which, in turn, discourages them from taking the bike out for a spin in the future. In worst cases, an ill-fitting bike can even lead to damning injuries.

Therefore, if you want to create fond biking experiences, you have to invest in a bike that fits your body shape well and is of the right size. Today, we’ll discuss a few ways you can determine the correct bike sizes for your needs.

Thankfully, if you don’t have the confidence to discover your correct bike size, you can always seek help from a professional.

Having an expert measure your fit dimensions, sizing, and walk you through the intricacies involved with bike fits can make a world of difference. The expert will set you up with the right bike from the right bike shops and your cycling experience will be more pleasurable than you ever imagined.

For those looking to purchase their bikes online, here’s a useful guide on how you can determine the correct bike sizing.

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2 Things to Check to Get the Correct Bike Size

Rider Height Measurement

The easiest way to determine the correct bike frame size for your body is by measuring your height.

Stand against a wall and have someone mark the top of your head on the wall. Now, measure your height from the ground up all the way to the mark.

Inseam Length Measurement

It’s also a good idea to measure the inseam length (inside leg measurement) for a more accurate bike fit result. To do that, again stand against a wall. This time, have your feet positioned 6-8 inches apart.

Now, take a book and place it between your legs. Next, measure from the top of the book to the floor and you’ll find your inseam length (inside leg measurement).

Finally, use the rider height measurement and inseam length and identify the bike frame size type that’ll fit you best from the sizing guide provided below;

Bike Size Charts

Use the following guide to find the best road bikes and mountain bikes for you and your family. Remember that as long as you get the frame sizing correct, you won’t need to pay as much attention to the wheel size or saddle setback.

Road Bike Size Chart (For Men)

152-160 cm tall; 71-75 cm inside leg measurement48 cm (XX Small) road sized bike
160-170 cm tall; 75-79 cm inside leg measurement51 cm (Small) road or city bikes
170-174 cm tall;79-83 cm inside leg measurement54 cm (Medium) road bikes
174- 180 cm tall; 83-85 cm inside leg measurement 56 cm (Large) road bike size
180-188 cm height; 85-89 cm inside leg measurement57 cm (X Large) road bike size
188-195 cm height; 89-92 cm inside leg measurement60 cm (XX Large) road bike size
195 cm+ height; 92 cm+ inside leg measurement63 cm (XXX Large) road bike size

Mountain Bike Size Chart (For Men)

152-160 cm tall; 71-75 cm inside leg measurement15-inch (X Small) mountain bike frame size
160-170 cm tall; 75-79 cm inside leg measurement16-inch (Small) mountain bike size
170-174 cm tall; 79-83 cm inside leg measurement17-inch (Medium) mountain bike size
174- 180 cm tall; 83-85 cm inseam length18-inch (Medium) MTB size
180-188 cm tall; 85-89 cm inseam length19-inch (Large) MTB size
188-195 cm tall; 89-92 cm inseam length20-inch (Large) MTB size
195 cm+ tall; 92 cm+ inseam length21-inch (X Large) MTB size

Road Bike Size Chart (For Women)

148-152 cm44 cm (XX Small) road or city frame size
152-160 cm48 cm (X Small) road or city frame bike size
160-168 cm51 cm (Small) road or city frame bike size
168-175 cm54 cm (Medium) road or city frame bike size

Mountain Bike Size Chart (For Women)

148-158 cm13-14” inch mountain bicycle frame size
158-168 cm15-16” inch mountain bicycle size
168-178 cm17-18” inch mountain bicycle size
178-185 cm19” inch+ mountain bicycle size

Some Tips When Choosing a Bike Size

Your riding style can also play a factor in determining the correct bike size or bike type. For instance, as a mountain biker, if you want to ride aggressively and would prefer a bike that’s easy to maneuver, it may be in your best interest to go for a size smaller than recommended.

Also, if you’re into cross country racing and would like a bike that is flat and excels at speed performance, make sure to opt for a size larger than advised in the aforementioned make-shift chart.

While opting for a road or city bike, also pay in mind that you’ll need 1 inch or so of clearance over the top tube/ crossbar. For mountain biking, the bike should have 2-4 inch clearance.

Also, consider the top tube length of the bike before making a purchase. The top tube length is the length from the seat tube to the head tube.

Considering the top tube length gives you the opportunity to find a bike fit for your arm length.

Lastly, while buying a bike, don’t worry about the saddle height too much as that can always be adjusted.

How are Bikes Measured?

You have to understand how bikes are measured to understand a bike size chart fit and find the right size bike.

Bike manufacturers or bicycle brands commonly measure and categorize bikes according to their seat tube length (frame sizes). In most cases, the seat tube length measurement is taken from the center of the bottom bracket up to the top of the seat tube.

Seat tube length is arguably the best indicator of a bike stand over height. Too big of a stand over height and you can get a bruised undercarriage when you stop and ride off.

You’ll also notice that road bikes are measured in centimeters while inches are used to measure mountain bikes.


The best way for you to find the right bike frame size for your needs is to head to a bike shop and have an expert look after your requirements.

A few bike recommendations, pieces of advice, and proper bike sizing results will follow suit and you can review all the shortlisted bicycles through the “trial and error” process. Only then will you be able to figure out which bicycle works best for you.

However, if you aren’t planning to ride competitively and wouldn’t mind missing the mark a bit with bike fit and choosing the right bike, you can rely on the aforementioned bike sizing chart or bike size guide as a starting point in your new bike career.