Loudness Normalizer

Measure integrated loudness (EBU R128 / ITU-R BS.1770) and normalize to a streaming platform target.

Your files stay on your device. All processing runs in your browser using WebAssembly — nothing is uploaded to a server. You can disconnect from the internet after this page loads and it will still work.

Drop an audio file here
or click to browse
WAV, MP3, FLAC, OGG, M4A — anything your browser can decode.
2. Target loudness
-24 (quiet / broadcast) -9 (very loud)
Above -12 LUFS the limiter has to work hard, which can audibly pump or dull transients. Streaming platforms will also turn this back down to their own target, so the extra loudness is lost on playback while the processing stays.
3. Output
Your source sample rate and channel count are preserved — mono stays mono. Need FLAC, MP3 or a different sample rate? Run the WAV through the Format Converter.

Result

Input
LUFS
Output
LUFS
Gain
dB
Limiting
dB peak
Download WAV

Need this as FLAC or MP3, or at a different sample rate? Send it to the Format Converter.

What this does

Streaming platforms play everything back at roughly the same loudness. If your track is louder than their target they turn it down; if it is quieter, most of them leave it alone. Mastering far louder than the target therefore buys nothing on playback — the platform undoes it, and whatever dynamic range you traded away to get there stays lost.

This tool measures your file's integrated loudness across its whole duration, applies the gain needed to land on your chosen target, and runs the result through a mastering limiter with the ceiling fixed at −0.5 dBFS so nothing clips. It then measures the output again and shows you both numbers, so you can see it actually hit the target rather than taking it on faith.

How the measurement works

Loudness is measured per ITU-R BS.1770-4, the standard behind EBU R128. The signal is K-weighted — a high-shelf and a high-pass filter that approximate how human hearing weights frequency — then analysed in 400 ms blocks with 75% overlap.

Two gates then decide which blocks count. An absolute gate discards anything below −70 LUFS, and a relative gate discards blocks more than 10 LU below the average of what survived. This is what stops silence, fade-ins and quiet intros from dragging the measurement down, and it is why integrated loudness reflects how loud a track actually feels rather than its raw average.

Choosing a target

PlatformTarget
Spotify−14 LUFS
YouTube−14 LUFS
Apple Music−16 LUFS
Amazon Music−14 LUFS
Broadcast (EBU R128)−23 LUFS

If you are unsure, −14 LUFS is a sound default: it matches the most common streaming target and leaves the limiter with little to do on typical material.

Limitations, honestly