Improve your running form

What the tool measures

The YOUB running form analyzer evaluates a short video of your running style right in your browser. Automatic body detection measures overstride, knee flexion, trunk lean, cadence and vertical oscillation, and compares them against typical target ranges. Five metrics are calculated from the video. Each has a typical target range that serves as a rough guide, not a strict rule.

• Overstride / shank angle at contact: target range 0 to 12°. A notably higher value means your foot lands well ahead of your knee, which brakes with every step and adds joint load.
• Knee flexion at contact: target range 18 to 30°. Very straight can point to a hard landing, very bent can point to a bouncy, inefficient style.
• Forward trunk lean: target range 5 to 15° from the hips. Too upright slightly slows propulsion, a strong forward fold loads the lower back.
• Cadence: typically 160 to 185 steps per minute, though it varies a lot with pace, height and running experience.
• Vertical oscillation: typically 0 to 5% of estimated body height. An estimate only, since a single camera has no true calibration.

How to film it

Film yourself from the side, at a right angle to your running direction, with your whole body in frame. Camera roughly at hip height, phone upright so you fit in head to feet (landscape works too). 15 to 20 seconds of steady running is enough, a treadmill works especially well since you stay in place. Make sure the lighting is good and the camera doesn't shake.

Privacy and accuracy

The analysis runs entirely in your browser on your device, your video is never uploaded or stored. The values come from a single 2D camera view and automatic body detection, so expect an accuracy of roughly ±5 to 8 degrees. Only the body side facing the camera is evaluated. This tool is a form screening, not a medical or biomechanical lab analysis. For individual training decisions, the YOUB coach also factors in your training history, fatigue and goals.