magnetometer · magnetic flux density (µT) · transient detector
idle
Bx–
By–
Bz–
|B|–
Δ from base–
rate–
field transients (sudden Δ|B|)
What this is. The magnetometer reads quasi-static magnetic flux: Earth's field,
magnets, and low-frequency fields from currents (motors, transformers, chargers).
Move a magnet or charger near the device to see it respond.
What it is not. Sample rate ≤~60 Hz ⇒ Nyquist ~30 Hz, so radio, Wi-Fi, and lightning
RF sferics (kHz) are unobservable; only a very close strike's slow geomagnetic transient could register.
Requires a secure context (HTTPS or localhost) and a top-level page —
inside an embedded iframe preview the permissions policy may block the sensor.
Android Chromium only; iOS Safari does not expose the raw magnetometer.