Mp4gain Serial _top_ -

: It is designed to handle multiple files simultaneously, ensuring a consistent volume level across an entire media library. Security Warning regarding "Serials"

If you are comfortable with command-line tools, is the open-source powerhouse behind most normalization tools. It is 100% free and requires no serial. Mp4Gain serial

FFmpeg is the gold standard for multimedia processing. It is completely free and open-source. You can normalize volume using the loudnorm filter (EBU R128 standard). : It is designed to handle multiple files