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Mountain Bike Sizing Charts (What Size Do You Actually Need?)

By Sam Millers   /  Last updated - December 4, 2023

/ Overview / Buying Guide / Sizing / Types / Reviews /

Mountain Bike SizingFind your correct mountain bike size in about 15 seconds!

When buying a mountain bike, it is crucial to choose the right size. The wrong size will not only be uncomfortable but can result in serious long term effects to your back, shoulders, and wrists.

If you want to know which size you need, look below! Without making it too complex, we have provided the following chart which will work well in most cases.

Mountain Bike Size Chart

Rider Parameters Suggested Mountain Bike Frame Parameters
Feet & Inches Centimeters Inseam Length Centimeters Inches (Frame Size)*
4’10” – 5’2″ 148cm – 158cm 25″ – 27″ 33 – 37 13″ – 14″ (XS)
5’2″ – 5’6″ 158cm – 168cm 27″ – 29″ 38 – 42 15″ – 16″ (S)
5’6″ – 5′ 10″ 168cm – 178cm 29″ – 31″ 43 – 47 17″ – 18″ (M)
5’10” – 6’1″ 178cm – 185cm 31″ – 33″ 48 – 52 19″ – 20″ (L)
6’1″ – 6’4″ 185cm – 193cm 33″ – 35″ 53 – 57 21″ – 22″ (XL)
6’4″ – 6’6″ 193cm – 198cm 35″- 37″ 58 – 61 23″ – 24″ (XXL)

This sizing chart should work for every type of mountain bike type, but it is recommended to check each manufacturers personal preferences!

between two bike sizes

Please note: Some bike manufacturers may have different charts. This is because they have totally different frame designs. Always use manufacturer-specific sizing charts when possible.

If you’re between two bike sizes Read our recommendations. 

What If I Got My Bike Size Wrong?

First of all, you need to determine if you actually got the wrong frame size, or if you just need to make some minor adjustments.

  1. Is the saddle at the right height?
  2. Is the saddle at the right distance (back-forth)?
  3. Is the saddle at a correct angle?
  4. Do you have the right stem length and position?

Those small adjustments can have a big impact on the overall feel of your bike. Learn how to measure a bike frame from our guide in order to make sure that your bike is right for you.

Bike Fit

If you’ve done everything as mentioned and the bike still doesn’t feel like it is the correct size, you can think of returning the bike to get a more appropriate size by following the instructions recommended by each bike brand.

*Why not to entirely rely on XS to XXL?
Mountain bike frame dimensions from XS to XXL differ for every manufacturer.

There is no standard that says a 21” frame MUST be a size Large. For example, if a manufacturer makes only three sizes (S, M and L) the smallest frame can be designed to fit riders 5’6”– 5’10” (which is a medium on our chart).

Here is another example: We’ve seen that some manufacturers manufacture hardtail bikes in a XL size, and a full-suspension in an L size, but they both are meant for riders up to 6’6“. So, never rely purely on sizing labels (XS to XXL). Always size a bike using height AND inseam length.

What’s The Right Mountain Bike Saddle Height?

bicycle saddle height recommendation

For an even better result, order a bike fitting service. Through this service, they measure different points on your body and set the most optimal mountain bike saddle height for you. Make sure to get a professional bike fitting service if you are an aggressive rider and ride often!

How To Get The Best Riding Position?

Once you have the right frame size, you can get everything else in the right position.

Sometimes the exact right size mountain bike doesn’t feel right off the bat. This is because all of our bodies are different.

So what they can do here is adjust the saddle, buy a different angle/length stem, or move the handlebar position a bit. These are the easiest ways to optimize a mountain bike’s size.

Complete Bike Sizing Guide


About the Author

Sam Millers

Sam Millers is the guy behind Bikexchange.com. From the early days of three wheels to conquering challenging mountain trails, Sam's love for cycling knows no bounds. With a background in web development, Sam seamlessly combined two of his greatest passions – cycling and technology. As the creative force behind Bikexchange.com, he shares insightful stories, expert tips, and engaging content for fellow cycling enthusiasts. When he's not exploring new biking routes or tweaking website codes, Alex enjoys sipping on a post-ride espresso and planning his next cycling adventure.