About BikeSizeGuide
BikeSizeGuide compares the sizes brands publish for a rider’s height and inseam.
Guides are credited to the BikeSizeGuide Team. Size ranges help you narrow your options; the bike manufacturer’s official chart and the specific model’s geometry should guide your purchase.
Sources and model selection
Our tables, range charts, and finder come from the same brand sizing CSV. Each table links to the brand’s source and shows its fetched date. The build copies published ranges and labels; it does not estimate missing measurements, average brands, or fill gaps.
Road models: Trek Domane SLR (the captured Madone SLR chart is identical), Specialized Tarmac, Giant TCR Advanced Pro and Defy Advanced, and Cannondale SuperSix EVO. Giant’s road models stay separate because their ranges differ.
Mountain models: Trek Marlin, Specialized Stumpjumper, Giant Trance X, and Cannondale Habit. These have complete published height ranges. We omit Specialized Epic’s malformed source row and use Trance X so wheel-diameter labels are not mistaken for frame sizes. These are model examples, not charts for every bike a brand sells.
How matching works
Both published endpoints are included. At a shared boundary, or where ranges overlap, the finder returns every matching label. Nothing is trimmed to make a single answer. Giant’s combined result includes matching labels from either road model, with each model’s result shown underneath.
Imperial measurements are converted to centimeters for matching without rounding. Imperial table labels are approximate conversions of the published cm endpoints, rounded for reading; choose cm to see the original values. Switching units does not change the measurement used by the finder.
The “Across these brands” line uses only the smallest and largest published frame measurements among matching sizes. It describes those endpoints, not a continuous range of available frames. Giant has no frame cm values in this source, so its letter sizes do not contribute to that line.
Trek is the only brand here that publishes inseam ranges. Its inseam result is shown separately from height, without extending that data to other brands or inferring an inseam from height. If a measurement is outside a model’s ranges, we show “Not listed.”