Free tool

LUFS and true peak meter

Drop in a track and see its integrated loudness, true peak, peak-to-loudness ratio and loudness range, measured to ITU-R BS.1770-5: the standard Spotify says it uses to decide how loud your music plays.

Nothing is uploaded. The file is decoded and measured by your own browser; this page has no endpoint to send audio to. That's also why it works offline once loaded, and why there's no file-size limit beyond your device’s memory.

Drop an audio file, or choose one. It's read on this device and never sent anywhere.

If it needs to move

Fix a peak problem at the master

One contextual next step, offered after your result, never in front of it.

A reading over a platform’s target is turned down on playback, not damaged; a true peak over the ceiling is the one line that needs acting on, and the place to act is the mastering stage. Euphona’s AI mastering masters the mix to a loudness and true-peak target you can change, and reports the loudness, true peak and loudness range it measured before and after. The free plan runs it on your own track and plays the result back level-matched against the original.

See how AI mastering works

The numbers

What these numbers mean

What each reading is telling you, and the one that asks you to act.

LUFS measures how loud something sounds over time, rather than how large its waveform is. That's why a dense, compressed master can read louder than an open one that peaks higher, and why streaming platforms normalize by loudness rather than by peak.

Integrated loudness: One number for the whole track. Quiet passages below −70 LUFS are excluded, and so is anything more than 10 LU below the average, so an intro of near-silence doesn't drag it down. This is the number platforms normalize against.
True peak: The highest level the waveform reaches between samples, which is what a lossy encoder actually has to reproduce. It's usually higher than the peak your DAW shows, and that gap is why a master that looked fine distorts after upload.
Peak to loudness (PLR): True peak minus integrated loudness, in dB, as the EBU and the AES define it. A small PLR means the average sits close to the peaks, which is what heavy limiting does. No standard sets a target for it: it describes the master, it does not grade it.
Loudness range: How much the loudness moves across the track, in LU, from the quieter passages to the louder ones (EBU Tech 3342). A heavily limited master reads low; music with quiet and loud sections reads high. Neither is wrong, it describes the music.
Looking for a dynamic range meter?: PLR and loudness range are the two dynamics readings with a published standard behind them, and this page shows both. The EBU warns that loudness range is not the same as dynamic range or crest factor. The “DR” score some meters show is a proprietary measure, not a standard, so this tool does not compute it.
Being “over” a target: It means the platform turns your track down by that much. It doesn't mean the track is too loud, and turning it down yourself gains you nothing except the dynamics you gave up to get there.

Where the platform targets come from

Spotify, -14 LUFS integrated, ceiling -1 dBTP (-2 dBTP for masters louder than -14 LUFS). Published by Spotify in its guide for artists, “Loudness normalization”.
Apple Music, -16 LUFS integrated, ceiling -1 dBTP. Measured by third parties; Apple publishes −16 dB for Sound Check only in its podcast requirements, and asks for at least 1 dB of headroom in its Digital Masters guide.
YouTube, -14 LUFS integrated, no published true-peak ceiling. Measured by third parties; YouTube publishes no loudness figure and no true-peak ceiling.
Broadcast (EBU R 128), -23.0 LUFS integrated, ±0.2 LU, ceiling -1 dBTP. Published by the EBU in R 128 (2023). It is the level broadcast programmes are delivered at, not a player setting.

Read the longer explanation LUFS vs true peak How to make a song louder without clipping

Verification

How to check this tool

Measure the same file here and in whatever meter you already trust. They should agree to about a tenth of a LU; if they don’t, ours is the one to doubt and we’d like to know. On every build, this meter is tested against the test signals the EBU defines for loudness meters: Tech 3341 cases 1, 2, 5, 6, 9, 12 and 15 to 19 at 44.1, 48, 88.2 and 96 kHz, cases 3, 4, 10 and 13 at 48 kHz, and Tech 3342 cases 1 to 4 for loudness range. The tests build those signals from the EBU’s documents rather than using its audio files.