Check the integrated loudness and true peak of any audio file before you publish it
Processed in your browser. Nothing is uploaded. Checked against sources on 17 Oct 2026.Drop a song, voice-over or podcast and its integrated loudness appears in LUFS, measured with the gated method of ITU-R BS.1770-5, together with the true peak in dBTP found by four-times oversampling. Compare the reading with the platform you publish on: -14 for Spotify, -16 for Apple Podcasts, -23 for EBU broadcast. Changing the level is one more tap, and nothing is uploaded.
Drop your files or click to choose them.
Adjust the options and check the preview.
Download the result. Nothing was uploaded.
Peak normalising makes the loudest sample hit a level; loudness normalising makes the whole file sound as loud as a target. Streaming services and broadcasters work in loudness, measured in LUFS (loudness units relative to full scale), which is why two songs peaking at the same level can still sound very different.
Which target. Spotify turns every track to -14 LUFS. Apple Podcasts asks for about -16 LKFS with a true peak no higher than -1 dB. EBU R 128 sets European broadcast at -23 LUFS. Any value from -40 to -5 can be typed in.
What changes, and what does not. One gain is applied to the whole file, so the dynamics stay exactly as they were. Nothing is compressed or limited. When reaching the target would push the true peak above -1 dBTP, the gain stops at that ceiling and the page says which loudness it reached, so you can decide whether to compress the recording first. The result is a 16-bit WAV at the original sample rate.
The rest of the article, and all 6 questions about Audio Loudness Normalizer (LUFS), are on the Audio Loudness Normalizer (LUFS) page.
LUFS stands for loudness units relative to full scale. A meter weights the sound the way ears hear it, ignores silence and very quiet passages, and averages the rest, following ITU-R BS.1770. One LU is one decibel, so a file at -20 LUFS needs 6 dB of gain to reach -14.
Spotify adjusts tracks to -14 LUFS, according to its loudness normalization page. A louder master is turned down and a quieter one is lifted, as far as its peaks allow. Normalising to -14 here shows what listeners will hear, and keeps the true peak under -1 dBTP for lossy encoding.
Apple Podcasts recommends about -16 LKFS, plus or minus one decibel, with a true peak no higher than -1 dB FS. LKFS and LUFS are the same unit. Choose -16 here and every episode lands at the same level, so listeners stop reaching for the volume between shows.
Reaching the target would have pushed the true peak above -1 dBTP, which distorts after MP3 or AAC encoding. The gain stops at the ceiling and the page shows the loudness actually reached. Compress or limit the recording in an editor first, or switch the ceiling off if you accept clipping.
Rates and rules change; check the source before you rely on a figure.
Still stuck? Ask about Audio Loudness Normalizer (LUFS) and anybody who knows can answer. No account needed.
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