NoiseGauge - Sound Meter

NoiseGauge is a 100% software-only sound level meter that uses your iPhone's built-in microphone — no external hardware, no Bluetooth accessory, no MFi device required. NoiseGauge turns your iPhone into a real-time sound level meter. Measure ambient noise, monitor your surroundings, and know when the volume crosses into hearing-damage territory. FEATURES • Real-time dB reading with a large, readable gauge • Min / average / max statistics for the entire session • 30-second rolling waveform chart • Color-coded levels (safe green through dangerous red) • Noise reference table with real-world examples • Manual calibration if you have a reference sound source • Fully offline — no network, no tracking, no ads USE CASES • Check whether your office, bedroom, or study space is quiet enough • Evaluate noise in restaurants, gyms, concerts, and streets • Protect your hearing by knowing when it's too loud (WHO recommends avoiding prolonged exposure above 85 dB) • Compare noise levels between rooms or devices • Document noise complaints HOW IT WORKS NoiseGauge reads microphone input, computes the average power in dBFS, then applies a calibration offset to estimate sound pressure level (SPL). The default +100 dB offset works well for most iPhone models. You can fine-tune the offset against a professional reference meter if precision matters. IMPORTANT NOTE Smartphone microphones are not laboratory-grade instruments. NoiseGauge provides estimates suitable for general awareness, not regulatory or medical decisions. For compliance measurements, use a certified Type 1 or Type 2 sound level meter. PRIVACY Microphone audio is analyzed in real time and never recorded, stored, or transmitted. No analytics, no ads, no account required. SUBSCRIPTION INFO • Payment will be charged to your Apple ID account at confirmation of purchase. • Subscription automatically renews unless auto-renew is turned off at least 24 hours before the end of the current period. • Your account will be charged for renewal within 24 hours prior to the end of the current period. • You can manage and cancel your subscriptions by going to App Store → Account → Subscriptions. Privacy Policy: https://frexx.top/noisegauge/privacy.html Terms of Use: https://frexx.top/noisegauge/terms.html SUPPORT 475740640@qq.com