About Real Decibel Meter

What the tool measures

Without calibration it measures microphone input strength (a 0–100% mapping of digital dBFS). With a device-specific calibration offset it estimates environmental sound levels in dBA, dBC or dBZ. How results are calculated is documented in the methodology; limits in accuracy and limitations.

What it does not claim

There are no accounts, no servers receiving audio, and no claims of lab testing, formal approval or measured accuracy percentages — because none apply to browser microphones. The idle reading is “--”, estimates are labelled as estimates, and safety verdicts are never shown.

Publisher

Published by the Real Decibel Meter project at realdecibelmeter.com. Questions about using the tool: start with how to use or contact.