Mp3Decode - Version 2.3 If you're looking for a simple and quick way to turn to turn MP3s into .wav files, look no further than Mp3Decode. This freebie sports a clean interface and is a no-brainer to use. Just add the desired .mp3 files to its input box, specify the output folder, press the Decode button, and in just a few moments the .wav files are produced, ready to burn on a CD-R or modify in an audio editor.