Normalize Audio (LUFS Loudness Normalizer)
Normalize audio to a loudness target so every episode, song or clip plays at the same perceived volume. ProMedia measures loudness the way streaming services and broadcasters do (LUFS, ITU-R BS.1770), applies the exact gain to reach −14, −16, −19 or −23 LUFS, and uses a true-peak limiter only if peaks would clip. Batch-normalize MP3s and more in your browser, with no upload.
- Runs on your device
- Web Audio
- WebCodecs · GPU
- Works offline
Updated
Drop your audio files here
How to normalize audio loudness
Step 1: Drop one or many audio files on the box above.
Step 2: Pick a Loudness target: −14 LUFS for music streaming, −16 for podcasts, −19 for mono speech, −23 for broadcast.
Step 3: Press Normalize. The result card shows the loudness before and after, the gain applied and the true peak.
Good to know
Settings explained
- Loudness target
- −14 LUFS: Spotify, YouTube
- −16 LUFS: Podcasts, Apple
- −19 LUFS: Mono speech
- −23 LUFS: EBU R128 broadcast
Formats
Batch-friendly: add many files and they are processed one after another — if one fails, the rest still finish.
How it runs
- Web Audio
- Audio is processed with the browser’s built-in Web Audio engine, sample-accurate and fast.
- Hardware video engine
- Video is decoded and encoded by your device’s media hardware through WebCodecs — usually several times faster than real time.
What should I normalize audio to?
Use the target of the place your audio will be heard. Matching it means the platform has nothing to turn up or down, and your file sounds as you intended. If you are unsure, −16 LUFS is a safe middle ground for speech and −14 LUFS for music.
| Destination | Target | Setting here |
|---|---|---|
| Spotify and most music streaming | −14 LUFS | −14 LUFS |
| Apple Podcasts and most podcast apps | −16 LUFS, true peak ≤ −1 dB | −16 LUFS (default) |
| Mono speech podcasts | −19 LUFS mono plays about as loud as −16 LUFS stereo | −19 LUFS |
| European TV and radio (EBU R128) | −23 LUFS | −23 LUFS |
What does “normalize audio” mean?
To normalize audio is to change its overall level so it hits a chosen target. Nothing else about the sound changes: the same gain is applied to the whole file. What differs between tools is what they measure. Peak normalization looks only at the single loudest sample; loudness normalization, used here, measures how loud the whole file actually sounds to people, in LUFS (Loudness Units relative to Full Scale).
Peak vs loudness (LUFS) normalization
Peak normalization makes the loudest sample reach, say, −1 dB. Two files can hit the same peak and still sound very different in loudness, because one is a quiet acoustic track with one loud note and the other a dense pop song.
Loudness normalization measures integrated loudness over the whole file, with quiet passages gated out, so files at the same LUFS really do sound equally loud. That is why streaming services and broadcasters work in LUFS. This normalizer measures with the ITU-R BS.1770 method, and its true-peak ceiling (−1, −1.5 or −2 dBTP, under Advanced settings) keeps the result from clipping.
How do I make all my MP3s play at the same volume?
Drop the whole folder, keep one target (−14 LUFS suits a music playlist) and press Normalize. Each file is measured and adjusted on its own, so a quiet live recording is raised and a loud master is lowered until they match. If a file needs so much gain that its peaks would clip, the limiter shaves just those peaks, and the gain is re-measured so the target still holds.
Is normalizing audio bad?
No, as long as you do it once at the end. Normalizing is a gain change, with a limiter only when peaks would otherwise clip, so it does not add distortion; with Save as set to WAV or FLAC it is lossless. Two cautions: raising a very quiet recording raises its background noise too, and a high target on a dynamic recording leans on the limiter. Above about −9 LUFS most material starts to sound squashed, which is why no platform asks for that.
Tips & troubleshooting
Normalization is not compression: it will not even out a speaker who is loud in one sentence and quiet in the next. Clean noisy recordings with the noise reducer first.
Just need one file louder by a set amount? The volume booster adds a fixed number of dB.
Joining clips into one episode? The audio joiner matches loudness between them as it joins.
Normalize Audio (LUFS) FAQ
How many LUFS is too loud?
For distribution, anything much louder than −14 LUFS will just be turned down by streaming apps, and masters above about −9 LUFS usually sound squashed. For podcasts, −16 LUFS is standard; for broadcast, −23.
What is the difference between normalization and compression?
Normalization changes the level of the whole file by one amount. Compression reduces the difference between loud and quiet moments inside the file. This page normalizes; it does not compress dynamics.
Can I normalize MP3 files without re-encoding?
Not on this page. Changing the level here writes new audio data, so an MP3 is re-encoded at a bitrate close to the original. Choose WAV or FLAC under Save as for a lossless result.
Is my audio uploaded to be normalized?
No. Measuring and normalizing both happen in your browser on your device. Nothing is sent to a server.