mtb frame size calculator

Mountain bikes, or MTBs, are designed specifically for off-road and trail riding with best mtb tube. They share quite a few similarities with other types of bikes, however, their design is focused more on durability and performance when you’re riding on rougher terrains.

This calculator will recommend a mountain bike frame size based on your measurements. If you don't know your leg length, you will get a range of frame sizes to try out.

If you know how to use it, go ahead and fill in the rider info, otherwise we've explained all the ins and outs below.

Mountain Bike Frame Size Calculator


Rider Information

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How to use Our MTB Frame Size Calculator

Mountain bike frame sizes are slightly different and the units used in bike sizes vary depending on type and brand.Whereas road bike sizes are usually given in centimeters, mountain bike frame sizes are quoted in inches. Fortunately, our mountain bike size calculator takes away the guesswork as it suggests mountain bike frame size  in either inches or centimeters alongside manufacturers bike size charts.

This makes choosing the correct mountain bike frame size very easy. All you need to do is measure your height and your inside leg (inseam) and then enter those measurements into our  bike size calculator.

Measure your height

Simply stand on a flat surface, upright against a wall with your legs together and shoulders back. Make sure you take your shoes off. Place a pencil on top of your head and holding it parallel to the floor make a little mark on the wall.


Measure your inside leg

Stand with your back against a wall (no shoes). Place a book or ruler between your legs at your crotch. Get a friend to measure from the floor to the top of the book/ruler, making sure it is level.

leg length

Can I use the bike size calculator for women’s Mountain bikes?

Yes, typically women’s specific bikes have different bike frame sizes to unisex bikes, but they are sized in the same way. Women tend to have shorter upper bodies than men, so the frames are shaped differently.

Women's bikes tend to have shorter top tubes compared to a similarly sized unisex bike. This makes the bike slightly shorter than a unisex bike so a female cyclist will feel less stretched out on a women’s bike.

As this doesn’t affect the seat tube length (saddle height) or stand-over clearance, our bike size calculator is suitable for both unisex and women’s specific bikes and the information in this bike size guide is relevant to women’s road bike sizes as well as women’s mountain bike sizes.

What size bike should I choose if I am between sizes?

Sometimes our bike sizing calculator will recommend two different bike frame sizing options. This means that both the larger and smaller road bike frame size or mountain bike frame size recommended will be suitable It is a personal choice but, if you are unsure, there are a couple of rules of thumb:

Mountain bikes - choose the larger size. You don't want to feel too cramped on an MTB and lengthening the stem on a smaller bike can adversely affect the handling. You will better off with a slightly larger bike and shortening the stem if necessary, as this often improves handling.