"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.


- 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
- 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
- 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.
- WAVE graph with 2 display modes: Rolling & Buffer
- InstaDecibel to capture your dB report overlaid on photos and easily shared via popular social networks (Facebook, Instagram, Messages, etc.).
- Support both Portrait and Landscape layouts
- Beautiful, intuitive and carefully crafted UI design
- Optimized for iOS 11


- Standard time weightings (Response Time): SLOW (500 milliseconds) and FAST (200 milliseconds)
- Trimming calibration from -15 dB to 15 dB
- Standard measurement range from 30 dBA up to 130 dBA
- HISTO graph for plotted history of the recorded values
- 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
- "Keep Device Stay Awake" option for long duration recording
- Reset and clear current recording at any time
- Tap on Max value to reset at any time
- Pause/Resume the tool at any time


- 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.

Get Decibel X Premium and enjoy:
- Permanently remove all advertisements
- Unlock ITU-R 468, A, B, C frequency filters
- No limits when saving data

* Choose from different subscription options. Our standard subscription options are:
1-month Subscription
1-year Subscription

* Subscription payments will be charged to your iTunes account at confirmation of your purchase and upon commencement of each renewal term. Subscription with a free trial period will automatically renew to a paid subscription. You can cancel your subscription or free trial in the iTunes settings at least 24-hours before the end of the free trial period. The cancellation will take effect the day after the last day of the current subscription period and you will be downgraded to the free service.
* Please note: any unused portion of a free trial period (if offered) will be forfeited when you purchase a premium subscription during the free trial period.

* Privacy Policy:

What’s New

Version 8.1.1

Thanks for using Decibel X! Here's what's new for the version 8.1.1:
∿ Add WAVE recording and playback along with saved data
∿ Vastly improve data management and add new data exports: CSV, HTML, PDF and WAVE
∿ Add Map view to visually locate saved data
∿ Vastly improve Dosimeter interface
∿ Metadata changes
∿ Various other improvements & fixes

What to expect in the next version:
∿ Integrate with Health app
∿ Set notification and alarm when exceeded a preset threshold
∿ More powerful spectrum analyzer with support to customize: FFT size, windowing, octave

Ratings and Reviews

4.5 out of 5
499 Ratings

499 Ratings

Cianbean777 ,

Very good

Best decibel counter app I ever used. It’s strong points are everything. I would recommend it to anyone that wants to have accurate results. I want to know how to measure just the sound you want independently. For example, how would I just measure how loud I could scream without the background noise of the world, so I could JUST see how loud my scream was and nothing else??

iOS Expert ,

3 day trial, then €4.49 per month.

Nearly €54 per year to “subscribe” a decibel sensor app? Subscriptions are ruining the App Store, in my opinion. €4.50 per year for this kind of app? Maaaaybe. Per month? No way.

To make things worse Apple pretty much obfuscates “subscriptions” in Settings (hides them away). I used to be an app developer and needed to watch a video to uncover the location of subscriptions, so I could unsubscribe from this before being charged—less tech savvy users have more trouble unsubscribing surely. Borderline shady of Apple, if you ask me. They need to do better. I hope iOS 13 puts them in an easier to find location in Settings, where they should be. Not hidden away where they are now.

J10irl ,

Versatile db meter

Great little program to combat anther pollutant of our lives: Noise.
Allows you to identify major polluters and make your surroundings quieter.
Many other uses too. And the makers keep on improving the app!
Many thanks.


SkyPaw Co. Ltd
45.6 MB

Requires iOS 9.0 and watchOS 4.0 or later. Compatible with iPhone, iPad and iPod touch.


English, Dutch, French, German, Italian, Japanese, Korean, Portuguese, Simplified Chinese, Spanish, Traditional Chinese, Vietnamese

Age Rating
In-App Purchases
  1. PRO Upgrade €3.49
  2. Data Export €3.49
  3. ITU-R 468, A, B, C Weightings €2.29


  • Family Sharing

    Up to six family members will be able to use this app with Family Sharing enabled.

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