Road bike fit calculator and size guides
Compare road frames by stack, reach, and cockpit setup instead of a height chart. The calculator models saddle height, saddle setback, saddle-nose-to-hood reach, and bar drop for every published size, then shows the stem and spacer setup each size needs.
How road bike fit is calculated
Road fit assumes drop bars with the lowest, longest front end of the three disciplines: bar-drop targets run deeper than gravel or XC, and stock assumptions use a -6° stem in road-typical lengths. Race and endurance families are scored by the same engine, but their geometry lands in very different parts of your setup window.
Between two close sizes, the better pick is usually the one that reaches your target position with a moderate stem and spacer stack. If a size only works slammed or with an extreme stem, the report flags that compromise instead of hiding it.
road bike sizing guides
Open a model page for the full geometry table and size-specific answers, or start the calculator with the frame preselected.
This bike leans toward an aggressive front end, faster steering, and a more performance-oriented position.
This bike leans toward a taller front end and a more sustainable position for longer rides.
FAQ
What size road bike do I need for my height?
Height only narrows the range. Two road frames sold for the same height can differ noticeably in stack and reach, which changes cockpit reach and bar drop. Enter your measurements in the calculator and compare the sizes directly.
What is the difference between race and endurance road fit?
Race frames run a lower, longer front end for a deeper position; endurance frames run taller and shorter for a more sustainable one. The calculator scores both against your body, flexibility, and posture target, so you can see which family matches how you actually ride.
Does the calculator use real road bike geometry?
Yes. Every model page uses published stack, reach, top tube, and head tube numbers plus stock stem and crank assumptions, and the fit report is computed from those numbers for each size.
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