Loudness meter FAQ: LUFS, true peak and the Loudmeter apps
Short answers about Loudmeter Online and the Mac and iPhone apps. Platform targets are in the loudness targets table.
Online Analyzer
Is my audio uploaded anywhere?
No. Your file is decoded, measured and played back in your browser. Nothing is sent to a server.
Which file formats work?
WAV, AIFF, MP3, M4A (AAC and ALAC) and FLAC.
Can I hear my song the way Spotify or Apple Music will play it?
Yes. After the analysis, press play under Hear it on streaming and pick a service: Spotify, Apple Music, YouTube, Amazon Music, TIDAL, Deezer or SoundCloud. Your file plays at the level that service would use, and you can switch while it plays to compare with the original. Each service's qualities are there too: lossless plays your original samples, and lossy ones are encoded in your browser with the service's codec and bitrate. Nothing is uploaded.
Which standard does it measure to?
ITU-R BS.1770-5 and EBU R128: integrated, short-term and momentary LUFS, true peak with 4× oversampling, and loudness range (LRA).
Can it meter live while I mix?
No. The online analyzer measures finished files. For a moving number while you mix, use LOUDMETER: Menu Bar on your Mac, which meters whatever your Mac is playing.
Why do two loudness meters show different LUFS?
Two meters that follow ITU-R BS.1770 read the same integrated LUFS for the same file, to rounding. A gap almost always means a different setup: a selection instead of the whole file, gating switched off, a momentary reading compared with an integrated one, or one channel measured instead of two (about 3 LU quieter). True peak is the one reading that can legitimately differ a little between meters.
Is there a file length limit?
Only your device's memory: the browser decodes the whole file before measuring it. Songs, stems and episodes are fine. For very long files, such as a 90-minute recording, use the Mac app.
LOUDMETER: Menu Bar (Mac)
Does Loudmeter need a DAW plug-in?
No. It measures the audio your Mac sends to your monitor output, so you can meter your DAW, Spotify or the browser without adding a plug-in. It can follow supported physical output routes even when your DAW uses a different output than macOS.
Can I analyze an audio file?
Yes. Drop an MP3, WAV, AIFF, FLAC or M4A file onto the panel for offline analysis, compare it with Spotify, Apple Music, YouTube, Netflix and EBU R128 targets, then copy the results or export a PNG report.
Can I stop some apps from being measured?
Yes. In Settings, Ignore Apps lets you choose apps LOUDMETER should not hear, such as a video call or your mail app. Everything else on your monitor output is measured normally, and plug-ins inside a DAW count as part of that DAW.
Can it warn me about clipping or phase problems?
Yes. Optional macOS notifications alert you when true peak goes above 0 dBTP, when LRA drops below 4 LU (over-compression) or when correlation drops below −0.3 (phase).
Which macOS version is required?
macOS 14.4 or later.
How much does it cost?
$9.99 on the US App Store, as a one-time purchase with no subscription. Prices vary by country. The online analyzer and the iPhone and iPad app are free.
LOUDMETER: LUFS Meter (iPhone & iPad)
Do I need a Mac to analyze a file?
No. File analysis runs on your iPhone or iPad. Live mode connects to LOUDMETER: Menu Bar running on a Mac on the same local network.
What does the iPhone app measure?
Integrated LUFS with short-term and momentary maxima, true peak with an over count, loudness range, PLR, stereo correlation and a loudness timeline, plus Spotify, Apple Music, YouTube, Netflix and EBU R128 targets. It is free.
Does the app upload my audio?
No. File analysis runs on your device. In Live mode the Mac sends meter readings over your local network, never audio.
Which devices are supported?
iPhone and iPad with iOS or iPadOS 17 or later.