Bike Size Chart: Find Your Bike Size by Height and Inseam
Enter your height and inseam to get a bike size recommendation, then compare Trek, Giant, and Specialized sizing before you buy.
Enter your measurements to see your recommended size, backup size, confidence, and why it fits.
Road
Find road bike frame sizes by height, inseam, and fit preference.
Gravel
Check gravel bike sizes with clearance and between-size guidance.
Bike Size Calculator
Use the calculator for road, mountain, gravel, and kids' bikes when you need a recommendation now.
Homepage
Start from the homepage, then open the calculator or the dedicated road and gravel pages.
Find your size in 30 seconds
One measurement flow, brand-specific answers.
Bike Size Finder starts with height and inseam, then checks bike type and brand sizing so you do not rely on a generic chart alone.
01
Enter height and inseam
02
Choose bike type
03
Compare brand sizing
How recommendation works
Official charts first. Geometry when available.
We start with published size ranges, then use inseam, standover, stack, and reach to explain close calls.
FAQ
Short answers for riders choosing a size before purchase.
What size bike do I need for my height?
Start with your height range, then confirm with inseam. If you are between two sizes, bike type and riding style usually decide whether to size up or down.
Is bike size based on height or inseam?
Both matter. Height gives the first size range, while inseam helps check standover clearance and whether the frame will feel too tall or too small.
Should I size up or down if I am between sizes?
For road bikes, size down for a sportier fit and size up for a more relaxed fit if reach is comfortable. For gravel and mountain bikes, many riders prefer the smaller size for easier handling.
Are Trek and Giant bike sizes the same?
Not always. The same rider height can map to different labels across Trek, Giant, and Specialized, especially when one brand uses S/M/L and another uses centimeter sizing.