Whether you’re monitoring workplace noise, checking how loud a concert is, protecting your hearing, or simply satisfying curiosity, your iPhone can double as a decibel (dB) meter with the right app. While iPhones don’t replace professional sound‑level meters, many apps are surprisingly accurate for everyday use.
Below is a list of the most popular apps to measure decibels on iPhone, along with what makes each one stand out.
How Accurate Are Decibel Meter Apps?
iPhone decibel apps rely on the device’s built‑in microphone. While they’re not certified for legal or industrial use, many apps are accurate enough for:
- Home noise checks
- Classroom or office environments
- Personal hearing safety
- Music and practice sessions
For best results, use apps that allow microphone calibration and avoid using phone cases that block the mic.
1. NIOSH Sound Level Meter
Best overall for accuracy and safety
Developed by the National Institute for Occupational Safety and Health (NIOSH), this app is widely considered one of the most reliable decibel meter apps available.
Key features:
- Professional‑grade algorithms
- A‑weighted and C‑weighted measurements
- Time‑weighted averages
- Noise exposure tracking
Best for:
Workplace safety, hearing protection, serious noise monitoring
2. Decibel X: dBA Noise Meter
Best for real‑time visuals
Decibel X is one of the most popular and visually polished sound meter apps on the App Store.
Key features:
- Real‑time decibel readings
- Frequency spectrum analysis
- Data export options
- Apple Watch support
Best for:
Everyday noise checks, content creators, musicians
3. Sound Meter – Decibel Meter
Best for simplicity
If you want a no‑frills decibel meter, Sound Meter gets the job done.
Key features:
- Instant dB readings
- Clean, easy‑to‑use interface
- Lightweight and fast
Best for:
Quick noise measurements, beginners
4. SPLnFFT Noise Meter
Best for advanced users
SPLnFFT offers detailed sound analysis beyond basic decibel readings.
Key features:
- FFT frequency analysis
- Calibration options
- Data logging
Best for:
Audio engineers, researchers, advanced hobbyists
5. Too Noisy Pro
Best for classrooms and groups
Too Noisy Pro is designed to provide visual feedback when noise exceeds set limits.
Key features:
- Customizable noise thresholds
- Visual alerts
- Kid‑friendly design
Best for:
Teachers, classrooms, group environments
6. Apple Watch Noise App (Bonus)
While not an iPhone app per se, Apple’s built‑in Noise app works alongside your iPhone.
Key features:
- Continuous background monitoring
- Hearing health alerts
- Health app integration
Best for:
Long‑term hearing protection and awareness
Comparison Table
| App Name | Accuracy | Best Use Case |
|---|---|---|
| NIOSH Sound Level Meter | ⭐⭐⭐⭐⭐ | Professional & safety |
| Decibel X | ⭐⭐⭐⭐ | Everyday & creative use |
| Sound Meter | ⭐⭐⭐ | Quick checks |
| SPLnFFT | ⭐⭐⭐⭐ | Advanced analysis |
| Too Noisy Pro | ⭐⭐⭐ | Classrooms |
| Apple Noise App | ⭐⭐⭐ | Long‑term monitoring |
Tips for Better Decibel Measurements
- Remove thick phone cases
- Calibrate the app if possible
- Keep the phone steady and pointed toward the sound source
- Avoid covering the microphone
Final Thoughts
If you’re looking for the best decibel meter app on iPhone, NIOSH Sound Level Meter is the top choice for accuracy and reliability. For everyday use with a modern interface, Decibel X is a strong alternative. Meanwhile, simpler apps like Sound Meter are perfect for quick checks.
No matter which app you choose, remember that smartphone decibel meters are best used as informational tools, not replacements for professional equipment.
