Audio Joiner is a free tool to trim and merge mp3 and other audio files. Features: 1. Trim and merge audio files such as mp3 into a single audio file. 2. Support all audio codecs installed in the system such as mp3, m4a, wav, flac, aac, alac, amr, wma, etc. 3. Support most popular output audio formats including mp3, m4a, flac, wav. 4. Display waveform graphs of the input audio files. 5. Able to preview the trimmed audio clips before join them together. 6. Easy to use. Free.