When your posture gives out
Average deviation against minutes into a session, pooled across 0 stored sessions.
3 minutes ago
below the dashed line is inside your tolerance
now
Not tracking
Calibrate once, then start a session.
- Alignment
- —/100
- Leading fault
- —
- Deviation
- —×tolerance
- Screen distance
- —cm as calibrated
- Elapsed
- 00:00
- Next break
- 30:00
Recent sessions
Share of each session spent inside tolerance. Larger dots had alerts.
Settings
Stored in this browser only.
The distance readout is anchored to this number. Measure it once with a tape and the figure means something; leave it at the default and treat it as relative only.
What this actually measures
A webcam sees you from the front. That makes four things genuinely measurable: how high your head sits above your shoulder line, how far it drifts off the midline, how much your head and shoulders roll, and how your distance to the camera changes.
It cannot see your lumbar curve or your true cervical angle, so Xerxes does not claim to. The distance figure is anchored to the one measurement you supply; everything else is a ratio against your own shoulder width, which is why it behaves the same on a 480p laptop camera and a 1080p external one.
When you turn your head, head metrics are suspended rather than scored — glancing at a second monitor is not a posture fault.
Video frames are processed by WebAssembly in this tab and are never uploaded, recorded or sent anywhere. The pose model is fetched once from a public CDN; after that the page works offline.