See whether your setup works with the current fit path.
The free online bike fit supports adult riders with road, gravel, or supported indoor-bike setups. You need a stable way to ride indoors and the ability to make—or arrange help with—one small change that can be undone.
Adult rider
Road, gravel, or supported indoor bike
An indoor stand that holds the bike while you pedal (trainer) or rollers
Enough room to record the full rider and bike
Stable compatible phone and mount
Willingness to complete indoor and real-ride follow-up
02FREE BIKE SIZING
Use free sizing for more bike types.
The size calculator covers common road, gravel, commuter, mountain, fat-tire, and electric-bike styles. That wider sizing support does not mean every bike type works with the current video-fit path.
Brand-neutral starting size range
Road, gravel, commuter, mountain, fat-tire, and electric-bike styles
Height and inseam inputs
No account or manufacturer catalog required
Clear comparisons to make before buying
03ROOM + PHONE
The room is part of the fitting setup.
A useful side view needs enough room to show you and both wheels without relying on an ultra-wide lens. The phone needs to stay level, straight, steady, and use a supported main lens.
Stable indoor bike stand or rollers
Phone mount or tripod
Clear side and front phone positions
Usable lighting and fitted riding clothing
Correct tools and manufacturer tightening instructions for the bike part
04NOT AUTOMATED
Some situations need a professional from the start.
Roth is not designed for injuries or diagnosed conditions, loss of bike control, advanced technical riding, uncertain mechanical limits, or adjustments outside the areas listed here.
A new injury, worsening symptoms, weakness, or loss of control
Medical diagnosis, treatment, recovery, or injury prevention
Shoe-cleat changes, racing-aero positions, advanced mountain biking, or downhill riding
A bike or part that cannot make the suggested change safely
A room or phone setup that cannot produce two clear, matching side recordings
If Roth cannot continue, that is not a diagnosis. It simply means the online process should stop and you should contact the right fitter, mechanic, or healthcare professional.