Sound Meter: dB Noise Meter

Sound Meter turns your phone into a fast, accurate decibel meter, a true SPL meter (sound pressure level meter) and noise meter you can trust for everyday noise checks. Whether you're checking workplace noise levels, sizing up a concert, tracking traffic outside your window, watching over a baby's room at night, or troubleshooting a noisy HVAC unit or machine, Sound Meter shows you exactly how loud things really are, in real time, with a clean always-dark gauge that's easy to read even in a dark room. Live decibel meter • Big, live dB readout on a NIOSH-coded color gauge, green under 70 dB, sliding through yellow and orange to red above 105 dB, so you spot the danger zone at a glance • Min, average, max and LEQ (equivalent continuous level) stats update as you go • Switch between dBA and dBC weighting, and Fast (125 ms) or Slow (1 s) response, just like a professional dB meter Rotating alarm bezel (new) • Drag the yellow arrow around the dial to set your own alarm threshold, in dB • Cross it and your phone vibrates and the readout turns red, perfect for keeping music, tools or a noisy room under a limit without staring at the screen Hearing protection, built in • A live "safe exposure time" estimate based on NIOSH/WHO guidelines, 85 dB is safe for about 8 hours, and that time halves every time the level climbs 3 dB higher • Turns abstract decibel numbers into a plain answer: how long can I stay here safely? Record, even in the background • Start a session and keep measuring while you use other apps, a foreground service with a persistent notification and stop button keeps recording alive, with a watchdog that auto-resumes if the system interrupts it • Only sound levels are recorded, never audio. Nothing is ever listened to, stored as a recording, or transmitted anywhere History, sharing & export (new) • Full recording history with a scrolling waveform view • Share a session as a premium, always-dark stats image, graph, key numbers and a QR code, ready for a report or a quick message • Export the full session as CSV for spreadsheets and further analysis • Turn any recording into a short animated video of the dB graph, ready to share Built for real use • Calibration offset slider (−15 to +15 dB) to correct for your phone's microphone • More than 70 in-app languages • Tablet and Chromebook layouts Honest by design Sound Meter is free and shows ads: a small banner and, now and then, a full-screen ad. And no subscription: recording, history, CSV and video export are all included, not locked behind a paywall. Your phone's microphone was never certified for acoustic measurement, so treat every reading as a well-calibrated estimate, not a medical or legally certified sound level meter. Use the calibration slider to bring it closer to a reference meter for your device, and use good judgment for anything safety-critical. Sound Meter, a noise meter and hearing-health companion for anyone who wants to measure noise, watch dB levels over time, and protect their hearing. Popular uses: an SPL meter with dBA and dBC weighting, record the noise level over time at a concert, in the office or during a loud night, check safe exposure times based on NIOSH and WHO limits, and set a vibration alarm at a dB threshold.