dB Decibel & Sound Meter Sendb

Sound Meter by Sendb is an Android sound level meter that measures loudness, frequency spectrum, and spectrogram directly on your device - no cloud, no account. Completely free, no ads, no subscription, no in-app purchases. No annoying interruptions - just open it and measure. FEATURES • Live level metering with dB(A), dB(C), and dB(Z) weighting, a color-coded level bar, and everyday sound references (e.g. "30 dB: Whisper") • Real-time frequency spectrum across 30 third-octave bands from 25 Hz to 20 kHz • Scrolling spectrogram with frequency and time axes • 60-second level trend graph • Single-point calibration against a known reference source for more reliable absolute readings • Session statistics: Leq, Min, Max, L10, L50, L90 • Microphone selection (e.g. when a device has multiple built-in microphones) • Light and dark theme • 14 languages, including Arabic with right-to-left layout PRIVACY The actual sound level measurement - weighting filters, FFT, level calculation - runs entirely on your device. No measurement data is ever stored or transmitted. Only your calibration value and app settings are kept locally; both stay on your device and are removed automatically when you uninstall the app. Full privacy policy: meter.sendb.day ABOUT Sound Meter by Sendb is an independent, non-commercial project - no ad network, no subscription model, no hidden costs. The measurement algorithms (A/C/Z weighting per recognized standards, FFT-based spectral analysis) were implemented independently based on publicly documented methods. Note: This app provides relative, or - after calibration against a known reference source - approximate absolute sound level readings. It is not a substitute for a calibrated precision sound level meter and is not suitable for safety-critical or legally binding measurements (e.g. occupational safety, noise compliance).