One camera at the pianist's side tracks the hips, legs, arms and every finger joint, and shows the angles live. Isolate one part, record the lesson, and send home a replay.
Free: 5 minutes of live camera tracking a day, no sign-up. Video files, YouTube analysis, recording and data export come with the Teacher plan. Runs in Chrome or Edge on a computer.
Is the bench too low? Do the feet reach the floor? Is the wrist dropping below the keys? Each of these becomes a number you can point to, track over time, and show a parent.
Torso to thigh: sitting too far in or perched on the edge.
shoulder · hip · kneeKnee higher or lower than the hip: the quickest bench-height check.
+ knee below hipWhere the feet are planted, and whether they reach the floor or pedal.
hip · knee · ankle · toeWrist above or below the elbow, relative to the keyboard.
0° = level forearmElbows pinned to the body or floating wide.
180° = straight armEvery finger joint on both hands, down to a collapsing fifth finger.
21 joints per handPlace a webcam or laptop at the pianist's right, about shoulder height and 2–3 m away, with head to feet in frame. Teacher plan: open a video you already recorded instead.
Tap Knee, Forearm or Pinky and everything else disappears, with the angle labelled right on the body.
Record with sound, then replay the skeleton alone in slow motion, chart any angle over time, and download the data.
Hide everything but the wrist and forearm while a student plays a scale, so they see exactly what you mean by "don't let it drop".
Record the same passage each month. The range of motion and average angles sit side by side in a spreadsheet.
Export a slow-motion skeleton video with no face or room visible, ready to share with families.
Open a lesson video, or capture a YouTube performance in another tab, and slow it to quarter speed.
All tracking runs inside the browser on your own machine. Nothing is uploaded: no video, no images, no angles. Recordings and data are saved only where you choose to download them. That makes it a comfortable fit for lessons with children.
The free plan lets you see live posture angles from your camera. The Teacher plan is everything you need to use it in real lessons: your own videos, YouTube performances, recordings, replays and data.
See it work, live from your camera.
Use it in every lesson, all year.
Secure checkout by Stripe. Renews yearly; cancel anytime and keep access until the end of the paid year.
A Mac or Windows computer with Google Chrome or Microsoft Edge, and a webcam or a video file. Phones and tablets are not supported yet.
At the pianist's right side, about shoulder height and 2–3 m (7–10 ft) away, so the whole body from head to feet is in frame. Posture angles are measured on the side nearest the camera.
No. Tracking happens on your computer. The only thing that leaves it is the subscription check with our payment provider, which uses your checkout email, never any video.
Yes. Click Sign in at the top of the page and enter the email you used at checkout. We email you a sign-in link; open it on that computer and your Teacher plan is on. No password needed, and you stay signed in.
Click "Manage billing" on the tracking page to open the Stripe billing portal. Cancelling stops the next renewal; you keep access until the end of the year you paid for.
No. It is a teaching aid that gives approximate angles from a single camera. It does not diagnose injury or replace a health professional.