How to Use the Online Decibel Meter
Three steps: allow the microphone, watch the live panel, tune and export.
Last materially reviewed: 2026-09-16
1. Allow the microphone
Press Start and accept the browser prompt. Use HTTPS; file:// and plain HTTP origins may block capture. Pick the input in the selector if you have several. If nothing happens, follow microphone troubleshooting.
2. Place the device and read the panel
Set the device on a stable surface at ear height, away from wind, vents and handling. Uncalibrated, the gauge shows input strength in percent — not environmental decibels. Current is the smoothed live value; Leq is the energy average; min/max bracket the session. Wait a few seconds for Fast/Slow smoothing to settle. For dBA estimates, calibrate your microphone first.
3. Tune, compare and export
Choose A-weighting for everyday checks (see dB vs dBA), compare against the decibel comparison chart, then export CSV for spreadsheets or JSON for code. History stays in this browser only (privacy).