Decibel Shield: the dB meter your iPhone deserves
Decibel Shield - dB Meter is a free iOS sound meter that shows live decibel levels, logs every measurement with history and trends, syncs with Apple Health and iCloud, and keeps measuring in the background. It holds a 4.7-star average across 528 App Store ratings.
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Download on the App Store — free
4.7★ average · 528 ratings · iOS 15.6+ · by APPSTACK LLC (ratings as of 2026-06-09)
What you get beyond the web meter
The free online meter on this site is a quick estimate. The app is the instrument: it stays running in the background, keeps your history, charts your exposure trends, and writes to Apple Health.
| Feature | What it does |
|---|---|
| Real-time decibel monitoring | Live dB readout with a dynamic VU meter view and dominant-frequency detection. |
| Exposure alerts | Get notified the moment noise crosses your set threshold, with age-adjusted safety levels. |
| Measurement history | Every session logged with date and time stamps, synced across devices with iCloud, exportable as CSV. |
| Apple Health integration | Save sound levels to the Health app alongside your other hearing data (Premium). |
| Trends | Insight into your sound exposure over the last week, month, quarter, and year. |
| Sound classification | The app identifies what it hears — speech, music, and more. |
| Location tagging | Remember where each measurement was taken. |
| Background measuring | Keep measuring while the app is in the background. |
| Calibration | Built-in device corrections, plus a fine-tuning slider to match a reference meter (Premium). |
| Noise & nature sounds | White, brown and pink noise plus fan, ocean, rainfall, water and forest sounds for masking and sleep. |
Honest answers
How much does Decibel Shield cost?
The app is free to download and measure with. Premium — which unlocks Apple Health sync, calibration fine-tuning, auto-save and more — is $44.99 per year after a 7-day free trial.
Does it show ads?
No. There are no ad networks in the app — no banners, no interstitials. The free tier is supported by the optional Premium subscription, nothing else.
Does it work offline?
Yes — sound measurement runs entirely on the device, so the meter works without an internet connection. iCloud sync of your saved readings happens when you are back online.
What data does the app collect?
Per the App Store privacy label, the app collects usage data and product-interaction analytics that are not linked to your identity. Audio is processed on-device for measurement.
What iOS version do I need?
Decibel Shield requires iOS 15.6 or later and supports iPhone and iPad.
Want to know how accurate phone meters can get before you download? Start with can your iPhone measure decibels accurately?