# SPLnFFT Noise Meter — Serious audio measurements

> Advanced sound level meter and frequency analyzer for iOS devices. (iPhone/iPad app by Fabien Lefebvre.)

- Source: https://appshunter.io/ios/app/splnfft-noise-meter/id355396114 (this page in markdown: same URL + `.md`)
- Developer: [Fabien Lefebvre](https://appshunter.io/developer/338004167)
- Category: Utilities, Music
- Price: $3.99 with in-app purchases
- Rating: 4.80/5 from 60 App Store ratings · 166 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.2 · 4 MB
- Languages: American English, French (France), German (Germany)
- Released: 2010-02-18
- Data updated: 2026-08-26
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/splnfft-noise-meter/id355396114/reviews.md

## What is SPLnFFT Noise Meter?

SPLnFFT is a sound level meter (noise meter) for your iPhone or iPad with many advanced features: frequency analyzer, frequency meter, test signal generator, dosimeter, ...

This soundmeter App is the only one for iOS recommended by the "Laborers' Health and Safety Fund of North America".
Here are extracts from other reviews:
"our favorite sound measurement app" SafetyAwakenings.com
"SPLnFFT is comprehensive, easy to use" TapeOp.com
You will find more reviews here: https://www.facebook.com/SPLnFFT

For daily use, a very simple interface displays the level of exposure: if orange or red, protect your ears !
Professional users will take advantage of a wide range of accurate and reliable measurements: Leq, peak, L10, L95, taktmaximal, frequency analysis, histogram, dosemetering, ... A&C weightings are compliant with ANSI® S1.42 standard. "468" refers to ITU-R 468-4

*** Some KEY INFORMATION *** :
- you absolutely need to allow access to microphone to use this App
- screen rotation must be un-locked
- there are built-in help messages (speech bubble). Need more ? Contact us !: email, blog, Facebook,...
- do not expect to measure as low as 0dB(A) in a quiet room, for these 2 reasons: 30-130dB(A) is the standard usable range for sound level meters and anyway a standard quiet room is around 30dB(A) whereas a typical anechoic chamber is 10 to 20dB(A)

Top digital display is for measurement of sound power in 'slow' mode (averaged on 1s). Central analog display is for 'fast' mode (averaged on 1/8th s). But it can display 'slow' mode as well on request: just click on 'fast' label.
Peak and average values are displayed below and are held until you touch the 'reset' label. The videos on Youtube reveal more details.

Bottom view is a real time FFT (frequency analysis). You will notice that predominant frequency and next one are highlighted. Their frequencies and relative power are displayed on the right. If your input signal is a pure tone then this App will lock on its frequency and display a very accurate result.
Green line is the result of a real time FFT done with 1024 points. Purple line is the averaged FFT (exponential filtering done on power of each frequency). Blue line is a copy of what the purple line was when the user froze the display the last time.
A test tone at 1kHz or a white noise or a pink noise can be generated and sent to right and/or left outputs (select the type you want in BEEP tab). This FFT view - more precisely an upsized version of it - can be exported as a picture in your own photo library, using the camera button (when display is frozen only).  This picture can be exported in a mail as well.
The display can be flipped upside-down to ease reading: just rotate your iPhone while holding it vertically.

As for ALL sound meters (thus including this one and all others at any price), calibration is suggested if you want to reach extreme precision. This is enabled in this App thanks to a slider to apply some compensation and to three non volatile memories (choice to be made in MIC. tab). How to ? For calibration, you need and external reference, either a calibrated sound meter, or a calibrated noise source.
Note as well that the tiny embedded loudspeaker cannot reproduce extreme frequencies. Thus if you want to hear a real white or pink noise, you will need to use a quality headphone or HiFi system.

This App was designed seriously for our own needs, by a signal processing expert, and is regularly updated to maintain accuracy and reliability.

***** Any comment, any feedback ? Click on 'support' in iTunes: there is a blog for this. You can even contact us directly by email  or through the dedicated FaceBook page (note 'send email' top right) *****

## Key features

- Sound level meter (noise meter)
- Frequency analyzer
- Frequency meter
- Test signal generator
- Dosimeter
- Leq, peak, L10, L95 measurements
- Real-time FFT analysis

## Pricing and in-app purchases

Base price: $3.99.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Export raw data to Dropbox + PRO features | $4.99 | one-time |


## Chart rankings

- #102 in Top Paid · Utilities (US App Store)

## What do users think of SPLnFFT Noise Meter?

Overall sentiment: positive

**Pros**

- ⭐ Highly accurate sound measurements compared to professional equipment
- 🎯 Professional-grade features at affordable price point
- 📊 Comprehensive FFT and frequency analysis capabilities
- 🎨 Clean, intuitive, and visually appealing interface
- 🔧 Multiple weighting options (A, B, C, ISO-498) and response times
- 📱 Works reliably across multiple iOS devices and versions
- 🛠️ Built-in calibration tools for improved accuracy
- 👨‍💼 Responsive and helpful developer support
- ⏱️ Real-time SPL monitoring with min/max/average tracking
- 🎵 Useful for diverse applications (studios, live events, workplace safety)
- 📈 Stable and consistent performance over years of use
- 🔄 Regular updates and feature improvements

**Cons**

- 🎤 Microphone gain stuck on auto with built-in iPhone mic
- 📞 Limited customer support accessibility (Facebook-only contact)
- 🔄 Persistent review request pop-ups despite already reviewing
- 📱 Display text sizing issues on some devices (iPhone 11)
- 🌐 No website or email support outside of Facebook
- ⚙️ Steep learning curve for non-audio professionals
- 🔗 Dead OSHA reference link in app
- 📊 Limited data export options (CSV only)
- 🎬 Cannot record audio with video/dB levels simultaneously
- 🔋 Performance issues on older devices (iPad slowdown reported)

**Commonly reported bugs**

- Microphone gain slider unresponsive/locked on auto
- Landscape mode gets stuck, preventing setting changes
- Text display cropped on iPhone 11 (showing '10...' instead of '100.1')
- App freezes and requires reboot on some devices
- Review request pop-up appears repeatedly even after review submitted
- Rotation setting notification appears on every app launch
- iPhone 5s detected as iPhone 6 (potential calibration impact)
- iPhone 6 support not included in updates
- Readings drift to zero periodically on older iOS versions
- Settings reset when app is closed (dB mode reverts)
- Dead hyperlinks (OSHA reference)

**Most requested features**

- Ability to override automatic microphone gain control
- Recording functionality with audio and dB level overlay
- Landscape mode support with full FFT display
- Extended frequency range (down to 20Hz for 3rd octave analysis)
- Microphone frequency calibration curve adjustment
- Waterfall diagram with spectrum replay capability
- SIL scales (e.g., SIL4) support
- Silent alarm for loud environments
- Video recording with dB level overlay
- Ability to save and replay FFT spectral data over time
- Better app icon design
- Tutorial or help documentation for acoustic terminology
- Default email address field for result sharing
- Bluetooth audio input support
- Bar graph scale and cursor labeling improvements

## Recent user reviews (10 of 166)

All indexed reviews: https://appshunter.io/ios/app/splnfft-noise-meter/id355396114/reviews.md

### 3/5 — Stop working

*2026-07-17*

After about a year the app no longer works on my iPhone.

### 3/5 — Sound meter

*2026-02-19, version 7.1*

I bought this app and paid for it. The data is not possible to save. The Dropbox link goes nowhere and cannot be changed. A picture is not very useful. I am told I have to pay for advanced features. What are they? Why am I not asked in advance? I fear that I will pay twice for the same thing.

### 5/5 — Amazing

*2026-01-11*

I’m a full time sound engineer. Yes I have calibrated RTA mics and room measurement software, but I’ve compared this app side by side with those tools and this is perfectly usable and more than accurate enough for most situations.

### 5/5 — Indispensable

*2025-12-08*

Je l’ai acheté ily a bien des années et il me sers à chaque prestation pour régler l’EQ et volume. Aussi pour éliminer un Larsen en reconnaissant la fréquence coupable. 
À la maison je l’utilise pour régler les volumes de mes bandes orchestres. 
Un petit investissement pour cette app devenue indispensable dans ma “boîte à outils” :-)

### 5/5 — Music

*2025-11-29*

Working in bars and loud music I found this app invaluable.

### 4/5 — Interface à revoir

*2025-09-14*

Bonjour , l outil a beaucoup d options et de menu et sous menus trop pour les non professionnels qui veulent juste mesurer le volume sonore en amateur. L
Interface devrait avoir 2 modes un avance et un basique . Une autre chose on ne sait pas ou voir notre abonnement . Ça fait 30min que recherche l option subscription, je ne trouve rien 
Et donc je ne peux pas exporter ds Dropbox alors que j ai acheté l option ( je crois)

### 5/5 — It’s great, just mic gain auto query!

*2025-09-05, version 7.1*

It’s good, no issues.  I have a question i think i’m going to answer!  With the microphone gain set permanently to ‘auto’ ( i cannot move the slider!), is it impossible to stop this because it uses the inbuilt iphone mic?  Obvs, if the mic gain is auto-changing, i cannot realistically measure dB.  I had a noisy fan, i cleared debris from the grille…now it measures as louder in dB!  It’s much quieter to my ears than it was.  I look back at the screenshots, then find i cannot move the mic gain from automatic!  Now, some audio apps grab control of auto mic and circumvent it, do can noise meter be made to do this?  Thanks anyway.

### 5/5 — Very Good

*2025-07-03*

I use this many year no problem. I like it.

**Developer response:** Thanks for using this App and for feedback. Highly appreciated.

### 5/5 — Great product

*2025-04-23, version 7.1*

I’ve used this a great deal over the years for monitoring office machinery noise levels and taking appropriate action to ensure comfort for staff. I’d be stuck without such a tool.

### 5/5 — Multifunctional sound app

*2025-04-12*

I am NOT an expert in sound measurement, but I love this app for demonstrating to people who are skeptical of how loud our environments often are. The FFT feature is great for identifying noise sources as well. Lots of folks I’ve shown it to hav downloaded it themselves as well.

**Developer response:** Thanks for using this App and for feedback. Highly appreciated.

## Frequently asked questions about SPLnFFT Noise Meter

### What does the SPLnFFT Noise Meter app do?

SPLnFFT is a comprehensive sound level meter and audio analysis tool for iPhone and iPad. It offers features like frequency analysis, test signal generation, and dosimeter functions, catering to both casual users monitoring noise exposure and professionals needing precise acoustic measurements.

### What are the key features of SPLnFFT?

Key features include a sound level meter with real-time displays, frequency analysis via FFT, a test signal generator, and various professional measurement metrics like Leq, peak, and L95. It also supports A&C weightings compliant with ANSI standards.

### Is SPLnFFT free to use?

The app is free to download and use with basic functionalities. However, it offers in-app purchases for advanced features and professional-grade measurements, allowing users to unlock its full potential for more detailed audio analysis.

### What are the requirements for using SPLnFFT?

To use SPLnFFT, you must grant it access to your device's microphone. Additionally, screen rotation must be unlocked on your iPhone or iPad for optimal display and functionality. Built-in help messages are available within the app.

### What is the usable range for sound level measurements with this app?

The standard usable range for sound level meters, including this app, is typically between 30dB(A) and 130dB(A). It's important to note that measuring extremely low levels like 0dB(A) in a quiet room is not feasible due to ambient noise and the limitations of standard sound level meters.

## Version history (last 5 releases)

### 7.1 — 2023-12-24

No more long press to change frequency weightings.
Re-compiled for latest iOS. Better handling of various screen sizes and shapes.

### 7.0 — 2020-02-20

Optimized for latest iPhones and iOS.
Note that iPhone X and later do NOT support any more upside down orientation.

### 6.91 — 2018-10-15

Minor update for the HTTP GET feature: unique identifier added

### 6.9 — 2018-07-19

Broken links to external webpages repaired.
New set of durations for 'HTTP GET' feature.

### 6.8 — 2018-05-31

Native support of new kind of display as offered by iPhoneX for example.
New feature added in the advanced features pack: the ability to export main data regularly to a distant web server through a HTTP GET request.

## Apps similar to SPLnFFT Noise Meter

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Decibel X:dB Sound Level Meter](https://appshunter.io/ios/app/decibel-xdb-sound-level-meter/id448155923) | 4.6 (161,260) | Free | Utilities |
| [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 |
| [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 |
| [Shush - Sound & Noise meter](https://appshunter.io/ios/app/shush-sound-and-noise-meter/id1481271537) | 4.2 (323) | Free | Utilities |

## More apps by Fabien Lefebvre

- [Speaker Meter](https://appshunter.io/ios/app/speaker-meter/id338004164)
- [Diapason Audio Generator](https://appshunter.io/ios/app/diapason-audio-generator/id352091730)
- [logSPL](https://appshunter.io/ios/app/logspl/id491999427)
- [AeroGoto](https://appshunter.io/ios/app/aerogoto/id542983237)
- [BetonMix (concrete calculator)](https://appshunter.io/ios/app/betonmix-concrete-calculator/id872695788)

All apps by Fabien Lefebvre: https://appshunter.io/developer/338004167

## Related topics

[splnfft noise meter](https://appshunter.io/ios/topics/splnfft-noise-meter) · [splnfft](https://appshunter.io/ios/topics/splnfft)

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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 2026-08-26.*