Loudness normalization in online streaming services... are they using LUFS values to normalize to?

There's quite a bit of inaccurate information out there... one of those is how online streaming platforms are loudness normalizing the music playback.

NUGEN Audio has published this fine guide. But they're also spreading the "inaccuracy".

Those LUFS values do indeed give us a great idea of the "ballpark" that those services are at regarding loudness normalization, but in the "business of accuracy" that we audio engineers, and especially mastering engineers, are in, then using LUFS to predict how the normalization will be on those platforms is pretty much a shot in the dark, if you ask me.

The reason is simply that none of the services except Tidal is using LUFS. For instance then Spotify uses ReplayGain to loudness normalize.

That said then based on my experience with Youtube then the ballpark for them has constantly been VERY close to -13 LUFS so I can with confidence say that if you don't want them to turn down your master then deliver a -13 LUFS WAV master to the video editor. ...and then we just hope the video editor doesn't screw it up by summing the audio to mono or exporting the audio at a crappy quality... but that's another topic... kind of.

Good luck!