Loudgain is a loudness normalizer that scans music files and calculates loudness-normalized gain and loudness peak values according to the EBU R128/ITU BS.1770 standard (-18 LUFS).

loudgain will embed ReplayGain 2.0-compatible metadata tags in a file if requested but will not modify the audio data in any way.

loudgain supports the FLAC, Ogg, MP2, MP3, MP4, M4A, ALAC, Opus, ASF, WMA, WAV, WavPack, AIFF and APE audio formats. Video files with compatible audio streams are also supported.