Sound Level Meter (dBA / dBC)
Measure live sound level with A, C or Z weighting, Fast/Slow time weighting, Leq and max hold, with an optional calibration offset.
What this tool tells you
What it does
Use this to monitor rehearsal, studio, room or noise levels over time from a microphone.
How to use it
Pick a weighting, start the meter and let it run. Use Reset to restart Leq and max. Enter a calibration offset to convert relative readings to approximate dB SPL.
How to interpret it
Without calibration readings are relative to digital full scale. Uncalibrated phone and laptop microphones are not class 1 or class 2 instruments; use results for comparison, not compliance.
Frequently Asked Questions
- Is this a calibrated SPL meter?
- No. Browsers cannot know your microphone sensitivity. Set the calibration offset against a reference meter or calibrator for approximate dB SPL.
- What is the difference between A and C weighting?
- A-weighting follows human hearing at moderate levels and discounts bass; C-weighting is nearly flat and is used for loud or low-frequency noise.
- What is Leq?
- The equivalent continuous level: the steady level carrying the same energy as the varying sound over the measured time.
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