Bike size

The calculator estimates your frame size from your height and inseam, then maps it to the sizing scheme for the bike type — centimetres for road, and S/M/L for gravel and MTB. Inseam matters more than height alone because it drives standover clearance and saddle height.

Treat it as a starting point, not a verdict. Two riders of the same height can need different frames depending on torso and arm length, riding style and flexibility — which is why reach and stack, not just size, define modern fit. Use the result to narrow the range, then test-ride or get a proper bike fit.

Road and gravel bikes are usually labelled in centimetres or as S/M/L based on seat-tube length, while MTBs lean on S/M/L with a strong focus on reach and standover. Because geometries differ, the same rider is often a different 'size' across categories — always check the maker's geometry chart.

Between sizes, the smaller frame is more agile and easier to flick around, and suits a lower, sportier position; the larger frame is more stable and stretched out for comfort and long days. Your reach preference and flexibility usually decide it — when unsure, the smaller size with a slightly longer stem is the safer bet.