What LUFS is
LUFS — Loudness Units relative to Full Scale — is a perceptual loudness measurement defined by ITU-R BS.1770. It is the number streaming platforms normalise playback against, which is why it replaced peak metering as the figure that matters before you upload anything.
It is not a peak reading and it is not RMS. It approximates how loud something actually sounds, rather than how tall the waveform is.
DropWave reports integrated loudness — one figure for the whole file — measured to ITU-R BS.1770-4, gating included. That last part matters: the standard throws out silence and quiet passages before averaging, which is why a proper LUFS reading and a naive average of a file are different numbers.
Reading it
Loudness is negative. −9.4 LUFS is louder than −14 LUFS.
| Context | Roughly |
|---|---|
| Streaming normalisation | commonly cited around −14 LUFS |
| Modern club and electronic masters | frequently −8 to −6 LUFS |
| Broadcast (EBU R 128) | −23 LUFS |
| An unmastered mix | anywhere, often −18 or quieter |
None of these are rules. A loud master is not wrong — it will simply be turned down by anything that normalises, and the only thing the extra loudness bought you is less dynamic range at the same playback level.
What it is not
- Not a quality score. It is a measurement.
- Not momentary or short-term loudness. Those belong on a channel while you are mixing. DropWave answers "what is this finished file".
- Not loudness range. Not reported.
When there is no number
Loudness is undefined for material too short to measure and for a file of pure silence. In those cases DropWave shows nothing rather than inventing a figure.
Related
True peak — the other half of the pre-upload check · Loudness analyzer