# Decibel X:dB Sound Level Meter — Frequency Spectrum Analyzer

> Professional sound level meter and frequency spectrum analyzer for iOS devices. (iPhone/iPad app by SkyPaw Co., Limited.)

- Source: https://appshunter.io/ios/app/decibel-xdb-sound-level-meter/id448155923 (this page in markdown: same URL + `.md`)
- Developer: [SkyPaw Co., Limited](https://appshunter.io/developer/1842040687)
- Category: Utilities, Education
- Price: Free with in-app purchases
- Rating: 4.60/5 from 161,260 App Store ratings · 789 written reviews indexed
- Age rating: 4+
- Requires: iOS 13.0 · 86 MB
- Languages: American English, Dutch, French (France), German (Germany), Italian, Japanese, Korean, European Portuguese, Chinese (Simplified, China), European Spanish and 2 more
- Released: 2011-11-05
- Data updated: 2026-08-30
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/decibel-xdb-sound-level-meter/id448155923/reviews.md

## What is Decibel X?

"Decibel X" is one of very few noise meter apps on the market that has highly reliable, pre-calibrated measurements and supports dBA, dBC. It turns your iOS device into a professional sound level meter, precisely measures the sound pressure level (SPL) all around you. This extremely useful and beautiful tool will not only be a great tool for many uses but also bring you a lot of fun. Have you wondered how quiet is your room or how loud is a rock concert or sport event? "Decibel X" will help you answer all of those.

WHAT MAKE IT GREAT AND STAND OUT FROM OTHER APPS:

- Trusted accuracy: the app is tested and pre calibrated for all Apple devices. The precision is matching with real SPL devices
- Apple Watch support: see noise level right from your wrist
- Health App integration: export noise levels directly into Health app
- Frequency weighting filters: ITU-R 468, A, B, C, Z
- Powerful, smart history data management:
  + Recording data can be saved into a list of history records for future access and analysis
  + Each record can be exported as hi-res PNG graph or CSV text via sharing services
  + iCloud support which synchronize all history records across your Apple devices
  + Fullscreen mode to give overview the whole history of an record
- Dosimeter with NIOSH, OSHA standards
- Powerful calibration: Linear, Octave 1/1, 1/3, Load/save profile
- FFT and BAR graphs to display real time FFT. Those are very useful for frequency analysis and musical tests. Real time predominant frequency is also displayed.
- InstaDecibel to capture your dB report overlaid on photos and easily shared via popular social networks (Facebook, Instagram, Messages, etc.).
- Support Live Activity, Dynamic Island
- Support both Portrait and Landscape layouts
- Beautiful, intuitive and carefully crafted UI design. Themes: LIGHT, DARK and CLASSIC

OTHER GREAT FEATURES:

- Standard time weightings (Response Time): SLOW (500 milliseconds), FAST (200 milliseconds) AND IMPULSE (50 milliseconds)
- MIC Gain Offset from -50 dB to 50 dB
- Standard measurement range from 30 dBA up to 130 dBA
- HISTO graph for plotted history of the recorded values
- WAVE graph with 2 display modes: Rolling & Buffer
- SPECTROGRAPH
- Real time scale level chart
- Display Current, Average/Leq, and Max values with both nice and clear digital and analog layouts
- Quick reference text to help you compare with real-life examples

NOTES:

- Please do not expect a quiet room reading will be 0 dBA. The range 30-130 dBA is the standard usable range and an average quiet room will be about 30 dBA.
- Although all devices are pre-calibrated, custom calibration is suggested for serious purposes requiring higher precision and accuracy. You will need a real external device or calibrated sound meter as a reference, then adjust the trimming calibration until the reading matches with the reference.

* Privacy Policy: http://www.skypaw.com/decibelx/privacy_policy.html
* EULA: http://www.skypaw.com/decibelx/terms.html

## Key features

- Precise sound pressure level measurement
- Frequency spectrum analysis (FFT, BAR graphs)
- Historical data recording and export
- Dosimeter with NIOSH, OSHA standards
- Apple Watch and Health App integration
- Customizable calibration and filters

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Monthly Membership | $5.99 | per month |
| Annual Membership | $49.99 | per year |
| Weekly Membership | $1.99 | per 7 days |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Data Export | $2.99 | one-time |
| ITU-R 468, A, B, C Weightings | $1.99 | one-time |


## Chart rankings

- #196 in Top Free · Utilities (US App Store)

## What do users think of Decibel X?

Overall sentiment: neutral

**Pros**

- ⭐ Excellent app
- 👍 Easy to use and understand
- 🔍 Useful for various applications
- 🎓 Helpful for hearing protection
- 🔧 Accurate and reliable

**Cons**

- 💰 Expensive subscription model
- 🔒 Misleading free trial
- 📢 Intrusive ads
- 🤖 Inaccurate readings compared to professional meters
- 🤔 Confusing interface

**Commonly reported bugs**

- App crashes when deleting recordings
- Microphone issues on certain devices
- Saved files not accessible after updates

**Most requested features**

- Add GPS coordinates to recordings
- Improve reporting and data export
- Provide more weighting options
- Extend frequency range
- Allow music playback while using the app

## Recent user reviews (10 of 789)

All indexed reviews: https://appshunter.io/ios/app/decibel-xdb-sound-level-meter/id448155923/reviews.md

### 2/5 — Was excellent

*2026-08-25, version 9.9.5*

Was an excellent app for audio measurement until they put the C weighted curve behind a paywall. Won’t be paying £50 a year for this. I will be buying a pro meter. 
Great shame!

### 1/5 — Watch out for their terms and conditions

*2026-08-23, version 9.9.5*

They have been withdrawing money WEEKLy without my awareness !

### 2/5 — Fleeceware slop

*2026-08-20, version 9.9.5*

Annoying nagware

### 5/5 — Great sound meter👍

*2026-08-15, version 9.9.5*

I like this app because it can tell me other things that are as loud as my voice,

### 1/5 — Paid. Not free

*2026-08-13, version 9.9.5*

You have to pay for this.

### 1/5 — Hace to pay to use

*2026-08-12*

Useless

**Developer response:** Hi, Jorgekowalski! Thank you for your feedback. We understand that you may feel unpleasant with the app. However, please describe the situation more clearly. With our user-obsessed mentality, we shall continue to leverage and level up our standard features, advancing ones based on users' needs.

### 5/5 — Great to have a reliable noise app

*2026-08-10, version 9.9.5*

It is functional and greatly designed.

### 5/5 — Excellent app

*2026-08-09, version 9.9.5*

I am just using the free parts, but the work very well

### 2/5 — Not free - Long signup then holds you hostage to sign up

*2026-08-09, version 9.9.5*

Can’t use the app without signing up and starting three day free trial

### 5/5 — Ótimo

*2026-08-06*

5 estrelas

**Developer response:** Thank you for your feedback. We are happy that you like our App!

## Frequently asked questions about Decibel X

### What does Decibel X do?

Decibel X turns your iOS device into a professional sound level meter. It precisely measures the sound pressure level (SPL) around you and offers advanced features like frequency spectrum analysis and historical data management.

### What are the key features of Decibel X?

Key features include trusted accuracy with pre-calibrated measurements, Apple Watch support, Health App integration, various frequency weighting filters (A, C, Z, ITU-R 468), powerful history data management with export options, dosimeter functions, and real-time FFT and BAR graphs for frequency analysis.

### Is Decibel X free to use?

The app is free to download and use, but it offers in-app purchases for additional features and functionalities. This allows users to access core features for free while enabling advanced options for those who need them.

### What devices is Decibel X compatible with?

Decibel X is designed for iOS devices and is tested and pre-calibrated for all Apple devices. It also supports Apple Watch for convenient on-wrist monitoring and can integrate with the Health App.

### What are some common use cases for Decibel X?

Common use cases include measuring the noise level in your room, assessing the loudness of concerts or sporting events, conducting acoustic analysis, monitoring noise exposure for health and safety compliance (using dosimeter features), and for musical tests and frequency analysis.

## Version history (last 5 releases)

### 9.9.5 — 2026-04-04

Thanks for using Decibel X! Here's what's new for the version 9.9.5:
∿ [Fixes] - Fix an issue with restoring purchases in paywall screen
∿ [Fixes] - Fix an UI issue for the bottom tab bar
∿ [Improvements] - Support for new devices
∿ [Improvements] - Upgrade library components
∿ [Improvements] - Several other minor tweaks & bug fixes

What to expect in upcoming versions:
∿ Support external or bluetooth mics
∿ Hearing test

### 9.9.4 — 2025-09-30

Thanks for using Decibel X! Here's what's new for the version 9.9.4:
∿ [Fixes] - Fix a UI issue for the bottom tab bar
∿ [Improvements] - Upgrade library components
∿ [Improvements] - Several other minor tweaks & bug fixes

What to expect in upcoming versions:
∿ Support external or bluetooth mics
∿ Hearing test

### 9.9.3 — 2025-09-17

Thanks for using Decibel X! Here's what's new for the version 9.9.3:
∿ [New Feature] - Support latest iOS 26 and new released devices
∿ [Fixes] - Fix a crashing issue when tapping on Settings twice
∿ [Fixes] - Fix a crashing issue when checking subscription status at launching
∿ [Improvements] - Upgrade library components
∿ [Improvements] - Several other minor tweaks & bug fixes

What to expect in upcoming versions:
∿ Support external or bluetooth mics
∿ Hearing test

### 9.9.1 — 2025-06-25

Thanks for using Decibel X! Here's what's new for the version 9.9.1:
∿ [New Feature] - Add Customer Center for easier managing subscriptions. You now can view/cancel/reqquest refund subscriptions right within the app
∿ [New Feature] - Give discounted offers for eligible customers
∿ [Fixes] - Fix an issue where spectrum graph showing incorrect scale in linear mode
∿ [Fixes] - Fix an issue where dragging instantaneous value label not movable in fullscreen mode
∿ [Fixes] - Fix an issue where wave graph occasionally not showing
∿ [Improvements] - Add support for newer devices
∿ [Improvements] - Upgrade library components
∿ [Improvements] - Several other minor tweaks & bug fixes

What to expect in upcoming versions:
∿ Support external or bluetooth mics
∿ Hearing test

### 9.9.0 — 2024-10-13

Thanks for using Decibel X! Here's what's new for the version 9.9.0:
∿ [New Feature] - Loud noise alert: notification alarm when exceeded a preset threshold
∿ [New Feature] - Quick PDF report: quick preview and ready-to-share report for current recording
∿ [New Feature] - HTML export now include audio files within zip file
∿ [New Feature] - Support previewing PDF/HTML/CSV before exporting
∿ [Fixes] - Live Activities and some UI issues for iOS 18
∿ [Fixes] - Incorrect start time in CSV report export
∿ [Improvements] - Saved data will use timestamp instead of response time for better post processing
∿ [Improvements] - Upgrade library components
∿ [Improvements] - Several other minor tweaks & bug fixes

What to expect in upcoming versions:
∿ Support external or bluetooth mics
∿ Hearing test

## Apps similar to Decibel X

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Decibel X PRO: dBA Noise Meter](https://appshunter.io/ios/app/decibel-x-pro-dba-noise-meter/id1257651611) | 4.7 (6,897) | $69.99 | Utilities |
| [Decibel : dB sound level meter](https://appshunter.io/ios/app/decibel-db-sound-level-meter/id1227650795) | 4.6 (36,118) | Free | Utilities |
| [Noise Guru: Decibel Meter](https://appshunter.io/ios/app/noise-guru-decibel-meter/id6444836813) | 4.6 (299) | Free | Utilities |
| [dB Meter & Spectrum Analyzer](https://appshunter.io/ios/app/db-meter-and-spectrum-analyzer/id733773616) | 4.7 (865) | $29.99 | Utilities |
| [Decibel Meter - Sound Analyzer](https://appshunter.io/ios/app/decibel-meter-sound-analyzer/id1579747105) | 3.5 (54) | Free | Utilities |
| [Decibel Meter Sound Level pro](https://appshunter.io/ios/app/decibel-meter-sound-level-pro/id6737704013) | 4.5 (28) | Free | Utilities |

## More apps by SkyPaw Co., Limited

- [Toolbox PRO: Smart Meter Tools](https://appshunter.io/ios/app/toolbox-pro-smart-meter-tools/id354112909)
- [Toolbox - Smart Meter Tools](https://appshunter.io/ios/app/toolbox-smart-meter-tools/id933528345)
- [Decibel X PRO: dBA Noise Meter](https://appshunter.io/ios/app/decibel-x-pro-dba-noise-meter/id1257651611)
- [Translator X: Text Voice Photo](https://appshunter.io/ios/app/translator-x-text-voice-photo/id1276098141)
- [Translator X PRO](https://appshunter.io/ios/app/translator-x-pro/id1276098150)

All apps by SkyPaw Co., Limited: https://appshunter.io/developer/1842040687

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-30.*