Bike Size Calculator

Your details

Children get a wheel-size recommendation instead of a frame size.
Frame-size formulas differ by discipline. Choose the type closest to how you plan to ride.
Stand against a wall without shoes for the most accurate reading.
cm
Stand with your back against a wall, feet 15-20 cm apart. Place a book spine-up between your legs and push it snugly against your crotch. Measure from the floor to the top of the book spine.
cm
Recommended frame sizeMedium
51-53 cm (20-21")

Seat-tube length range that fits your inseam

Generic size labelM
Saddle height (LeMond)71.5
Saddle height unitcm
Frame size (cm)51-53
Frame size (inches)20-21
Formula frame size54.3
54.3 cm
XXS / XS<44Small44-50Medium50-55Large55-59XL / XXL59+

Size M: 51-53 cm (20-21")

  • Your inseam of 81.0 cm maps to a M frame (51-53 cm (20-21")) on a road/gravel bike.
  • The discipline formula gives a raw frame size of 54.3 cm, which rounds to the M band.
  • Set your saddle height to 71.5 cm from the centre of the bottom bracket (LeMond method). This is your most important fit adjustment.
  • Frame size is a starting point. Handlebar reach, stem length, and saddle setback all affect how the bike actually fits.

Next stepFor road bikes, 2-5 cm of stand-over clearance is typical. If the frame feels too tall, drop one size.

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