Live Demo — Synthetic Magnetometer

Simulated data

Runs entirely in your browser — no hardware required. Synthetic data in the NextMAG live-feed format, processed by a real FFT spectral engine.

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Current readingsSimulated data
Total field (Bt)
dB/dt (1-min)
Dominant freq
GIC risk
FFT spectrum — amplitude (dB re 1 nT) vs frequency (Hz)Simulated datanoise floor

Toggle Grid EMI to see the mains fundamental and its harmonics appear; switch 50/60 Hz to watch the comb shift. "Inject spike" adds a broadband transient; "storm" raises the noise floor.

Spectrogram — frequency (vertical, 0–320 Hz) over time (scrolling →)Simulated data
Freq (Hz)060120180240300
+20+5-10-25-40-50Power (dB re 1 nT)
144 stime (scrolling →)0 s (now)

Horizontal bands are the mains harmonics; toggling 50↔60 Hz or storm mode shifts/raises them in real time. 144 s history · harmonics of 60 Hz marked

Total field (nT)Simulated data
Rate of change dB/dt (nT/min, 1-minute cadence)Simulated data

Computed as |Bt(t) − Bt(t−60s)| per NOAA/NERC convention (thresholds like 10/30/100 nT/min assume 1-minute sampling), so it reads 0 for the first minute while a baseline accumulates. Quiet conditions sit at a few nT/min; storm mode drives it — and the GIC (geomagnetically induced current) risk score — up.