MP4 MP3 Converter converts MP4 to MP3 and MP3 to MP4. It is an easy to use and ALL IN ONE audio converter software. MP4 MP3 Converter not only converts audio formats to MP3, but also extracts audio from AVI, ASF, WMV, MPEG-1, MPEG-2, QuickTime MOV, and Real Media files. It supports more than 100 audio and video files, and keeps ID3 tag when converting. It is possible to customize sample frequency, bit rate, channels, and quality of target files. The MP4 MP3 Converter could automatically normalize volume of MP4 and MP3 files so that the output files have the same volume. You can also change volume manually. The software supports batch conversion. MP4 MP3 Converter is full compatible with Vista and Windows 7.