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Decibel Meter

Press Start to measure relative loudness from the microphone. Numbers are not calibrated to a real SPL meter—useful for comparing “quieter vs louder” in the same browser session only.
dB SPL (relative)
Peak dB
Average dB

How to use

  1. Tap Start meter and approve microphone capture.
  2. Watch Current dB animate; Average smooths jitter; Peak stores the loudest instantaneous frame.
  3. Toggle Stop before switching rooms so sample buffers reset cleanly.

FAQ

How should I interpret the numeric readout?

It maps microphone RMS logarithmically with an offset (~+90 dB) so zeros sit near silence—do not cite these numbers alongside calibrated hardware SPL meters.

Overview

This replication follows the KeyboardTester decibel_meter_tool math: RMS per animation frame feeds 20 log10(rms), clamps into 0–120, then drives both numeric readouts and a thermal-style progress bar keyed to instantaneous energy.