The decibel(dB) value of this noise level meter or soundmeter might be vary compare with an actual Sound Meter(dB Meter). Features: - Indicates decibel by gauge - Display the current noise reference - Display min/avg/max decibel values - Display decibel by graph line - Display Elapsed time of decibel - Can calibrate the decibel for each devices NOTE: Microphones in most devices are aligned to human voice and the maximum values are limited by the hardware. Very loud sounds (~90 dB and more) may not be recognized. So please use it as just an auxiliary tools. If you need more accurate dB values, we recommend a actual sound level meter for that.