Best Overall Android and iOS: Decibel X (iOS and Android)
Apple App Store Rating: 4.6 stars, free, offers in-app purchases
Google Play Rating: 4 stars, $3.99
Decibel X is a free iOS/Android decibel meter app. This app is quite popular as it offers a variety of features. If you are asking what is the best free decibel meter app, then this is probably it.
This app is arguably the most accurate decibel meter app for android and iPhone.
In fact, Decibel X essentially turns your smartphone into a professional sound level meter.
The app is highly rated for its accuracy and easy-to-use interface on which it displays real-time sound level information in decibels as well as with beautiful waves and graphs.
This app is also supported on Apple Watch, so you can have easier portability.
Best iOS: NIOSH Sound Level Meter App (iOS)
Apple App Store Rating: 4.7 • 7.9K Ratings, Free
While not as popular as Decibel X, the NIOSH Sound Level Meter holds the distinction o being developed by the National Institute for Occupational Safety and Health (NIOSH), which adds a tonne of credibility.
The app was initially developed to measure noise levels in the workplace for safety and health professionals. Since then, NIOSH has made the app freely available to the general public. If you are looking for a free decibel meter app for your iPhone, then this is it.
Most Affordable iOS and Android: Decibel Pro – Frequency Analyzer & dB Sound Meter
Apple App Store Rating: 4.6 • 29.5K Ratings, free, offers in-app purchases
Google Play Rating: 4 stars • 1,729 Ratings, Free with ads, Pro version available
The DecibelPro Sound Level Meter is a professionally accurate sound level meter app. The app is available for Android and iOS and includes features such as:
Noise Dosimeter: Measure noise thresholds.
Hearing test: Test the condition of your hearing.
Create photos and videos: Embed ambient noise level graphs onto photos.
Spectrum analysis: Spectrum analyzer with more than 100 operating options.
One of the main advantages of this app is the fact that the free version is pretty good with limited intrusive ads.
Of course, there is also a pro plan that offers additional features such as popular sound weightings and the spectrum analyzer.
You can use the app for a wide variety of situations whether it’s just checking ambient noise or as a quality bass tester or equalizing different sound systems.
Best SPL Meter Apps For Home Theater
Sound pressure level (SPL) is an important consideration in your home theater. Sound pressure level is a measure of the level of pressure produced by the sound you are measuring.
It is the most commonly used indicator of the strength of sound. Below is a list of the best SPL meter apps for your home theater:
Decibel X
Again, Decibel X tops the list because it is simply the best app for measuring sound levels. This app turns your smartphone into a pre-calibrated, accurate and easily portable sound level meter.
SPL Meter
This one is for professionals and is regularly used to measure SPL in ways traditional SPL meters are used (ballistics, ranges, filters, and decay rates). Even though the app comes pre-calibrated for most mobile devices, it can be adjusted to match professionally calibrated meters.
Why Use Decibel Measuring Apps?
So, all the decibel charts and decibel scale charts presented so far give ideas as to how loud sound at a certain decibel may be. For example, 70 dB could be about as loud as city traffic or 140 dB may be as loud as a jet taking off.
However, different cities will have traffic with different noise levels and different jets may emit noise at different intensities when taking off. In other words, decibels are hard to gauge.
It’s certainly not as easy as estimating a pound of chicken or 10 inches of rope.
So, is there a way to objectively measure noises easily?
Yes, there is!
There are several decibel meter apps out there that you can simply install on your smartphone and use on the go!
How Do Decibel Meter Apps Work?
These decibel meter apps can measure the noise levels around you and make recommendations so that you can take smart action to protect your ears from noise-induced hearing loss.
These apps use the phone’s built-in microphone to collect noise from the surroundings, analyze the same and give real-time noise exposure data.
For better results, you can purchase an external, calibrated microphone such as the Rode VideoMic Me Directional Microphone.
FAQs
1. How accurate are Android decibel apps?
There are several applications that, when combined with a proper microphone, may provide an efficient and precise method of taking measurements. So, it depends on the microphone’s quality of measuring the audio and how well the application works.
2. How many dB should home theaters be set up at?
The best setup would be up to 75 dB SPL. That’s the industry standard, and it’s fairly loud and produces enough volume to drown out any ambient noise.
3. What dB is best for bass?
Individual listeners’ favorable bass levels range from -3dB (listener 346) to 14.1 dB. (listener 400). As for the ultimate balance between your mains and subs, most people believe that increasing the sub-level by 3 to 6 decibels sounds better, especially since most people listen at less than the reference level.
Ensure that you do not exceed the limit, as it can be dangerous for your ears. Carefully use the volume.
4. What is the 6db rule?
The 6 dB rule states that doubling the distance between a transmitter and receiver reduces the received signal by 6 dB. A 6 dB increase in the received signal is obtained by halving the distance between a transmitter and a receiver.
Recap
There are, of course, other apps for measuring decibel levels. We should note that while these apps are pretty good and are often pretty accurate, they are not a replacement for sound pressure level meters, decibel (dB) meters, noise meters or noise dosimeters. They are simply handy aids for everyday, non-professional use. Additionally, they should not be used as a replacement for good hearing healthcare.

Norvan Martin is the founder of BoomSpeaker.com. He is a professional Electronics Engineer and is passionate about home theater systems and AV electronics. BoomSpeaker was created as an online hub to share his knowledge and experiences as it relates to home theaters and home audio electronics.
My email: admin@boomspeaker.com
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