Giant ATX, what size fits


Hi, i was wondering if you can help me please, I’m interested in the Giant ATX 27.5 mountain bike, but in not sure what frame i need as it says S/M/L etc. I usually ride a 20" hardtail mountain bike.



Glad to help you, but need more info. How tall are you and what is your leg length? Leg length is the distance from the floor to your crotch. To measure it, take your shoes off and stand with your back against a wall with feet shoulder width apart. Put a large book between your legs, with its spine firmly up against your crotch. Have another person measure from the floor to the spine of the book. Share with us these two measurements and we’ll be able to help you narrow it down.


Thanks for the reply, 5ft 7/5ft 8, and 29", Thanks.


By our calculations, your measurements put you on about a 17" MTB. The ATX small is listed as 16" while the medium is listed as 18".

As is always the case, and especially for you since you’re mathematically in between two possibilities, you should head to a local shop to try them on for size since only you can decide what’s most comfortable. Try using our bike shop finder on the product page: