Stand barefoot against a wall with feet 6–8 inches apart. Place a hardcover book between your legs and pull it snugly against your crotch (mimicking a saddle). Measure from the floor to the top of the book's spine.
While pedaling, your knees should not hit the handlebars (too small), and your legs should not fully lock out at the bottom of the stroke (too large).
When standing over the bike's top tube with both feet flat, you should have at least 1 inch of clearance on a road bike and 2–3 inches on a mountain bike for safety. 3. Understanding Advanced Fit (Reach & Stack) bike buying guide size
Finding the right bike size is the most critical step in ensuring a comfortable, pain-free, and efficient ride. While manufacturers provide general charts, a perfect fit depends on your height, inseam, and the specific type of bike you are buying. 1. Start with Your Height
Road bikes are typically sized in centimeters (cm). 4'11" – 5'2": 47 – 50 cm 5'3" – 5'6": 51 – 54 cm 5'7" – 5'9": 54 – 56 cm 5'10" – 6'0": 56 – 58 cm 6'1" – 6'3": 58 – 61 cm Stand barefoot against a wall with feet 6–8 inches apart
If you are on the cusp, sizing down is usually safer as it offers better control and maneuverability. Sizing up is better if you prefer a more stable, less "twitchy" feel.
Mountain and hybrid bikes are typically sized in inches or categorical sizes (S, M, L). 5'0" – 5'4": 14 – 15 inches (Small) 5'5" – 5'8": 16 – 17 inches (Medium) 5'9" – 6'0": 18 – 19 inches (Large) 6'1" – 6'4": 20 – 21 inches (XL) 2. Measure Your Cycling Inseam While pedaling, your knees should not hit the
Kids' bikes are sized by rather than frame height. 12-inch: Ages 2–4 (approx. 2'10" – 3'4") 16-inch: Ages 4–6 (approx. 3'7" – 4'0") 20-inch: Ages 6–9 (approx. 4'0" – 4'5") 24-inch: Ages 8–11 (approx. 4'5" – 4'9") Pro-Tips for Buying