Normalize Audio Loudness with FFmpeg loudnorm
Bring audio to a broadcast-standard loudness level (LUFS) in one pass instead of eyeballing volume sliders or pumping the gain up until it clips.
Run ffmpeg -i input.mp4 -c:v copy -af loudnorm=I=-16:TP=-1.5:LRA=11 output.mp4 to normalize audio to -16 LUFS with a -1.5 dB true-peak ceiling.
01Command
Command
$ ffmpeg -i input.mp4 -c:v copy -af loudnorm=I=-16:TP=-1.5:LRA=11 output.mp402What it does
The loudnorm filter measures integrated loudness and applies gain plus peak limiting to hit a target in LUFS, the unit used by streaming platforms: -16 LUFS is a common target for stereo content (podcasts often use -16, YouTube roughly -14). TP=-1.5 sets a true-peak ceiling so nothing clips after normalization. The -c:v copy flag leaves the video stream untouched, so only audio is re-encoded.
03Risk
!Warning: loudnorm's single-pass mode is an estimate; for production work, run it once with print_format=json to get measured values and feed them back as linear normalization.
04Undo
✓No undo needed — this command does not change persistent state.
05Sources
- FFmpeg Filters Documentation: loudnormEvidence: Official loudnorm filter reference: I (integrated loudness, e.g. -16 for -16 LUFS), TP (true peak), LRA parameters.
Last verified: 2026-09-17 · Category: Media