Sound Level Meter is a professional-grade online sound measurement tool that uses your device's microphone to provide real-time decibel readings, frequency analysis, and comprehensive acoustic metrics directly in your browser.
What is Sound Level Meter?
Sound Level Meter is a free web-based application that measures ambient sound levels in real time using your device's built-in microphone. It outputs A-weighted, C-weighted, or Z-weighted decibel readings along with MIN, AVG, MAX, and PEAK metrics, a frequency spectrum visualization, and sound classification labels. The tool runs entirely in the browser with no installation or registration required, and is developed and maintained by the team at soundlevelmeter.org.
Key Features
- Real-time decibel monitoring — Instant readings with adjustable update intervals: Realtime (50 ms), Fast (250 ms), Slow (1 s), or Very Slow (2 s).
- Frequency analysis — FFT-based spectrum display shows real-time frequency distribution, helping identify dominant tones and acoustic characteristics.
- Multiple metrics tracking — Tracks MIN, AVG, MAX, and PEAK sound levels throughout a session, displayed with duration counter.
- Professional weighting filters — Choose between dBA (human ear response), dBC (flat response), and dBZ (zero weighting) for accurate measurement standards.
- Calibration offset control — Adjust measurements with a configurable dB offset and sensitivity slider (0–100%).
- Interactive visual charts — Includes a sound level history graph, bar meter, and frequency display for comprehensive data visualization.
- Sound classification — Real-time labeling of sound levels with common noise source references (e.g., quiet room, conversation, traffic).
- No sign-up required — Start measuring immediately after granting microphone permission.
