I feel like maybe I have missed something with Free MP3 Cutter Joiner. It feels like two separate programs that have been joined by an unpleasant interface which tries its best to confuse. It does what it claims, but poorly at best.
Kind of cutting
After loading Free MP3 Cutter Joiner, you are met with the "Cutter" side of the program. The interface is a mishmash of icons stolen from other programs that seem to have been compressed and then enlarged until they are so distorted and ugly that they are almost hard to look at.
Multiple functions are hidden under these icons, and it is only by referring to the poorly translated help menu on the developer's website that it is possible to work out how to make use of this simplistic tool.
To really rub salt into the wound, the waveform at the center of the page is a fixed image that is in no way related to the audio file you have loaded - selecting an audio file from the browse function (drag and drop doesn't work despite what it may look like), makes no difference.
When you are done with the painstaking task of slicing up whatever audio you have dropped into the Cutter, you can head over to the "Joiner". This is a little more user friendly, but only because if offers even less in the way of functionality.
After picking your files from the search function and ordering them in the Joiner, a single press of the start button will link everything in the list into a single MP3. It offers no editing tools, and the cuts between each piece of audio is more than a little abrupt - but it at least works relatively painlessly.
Lacking in function, ugly, and hard to use, Free MP3 Cutter Joiner has a very specific use. But given that Audacity is also free and offers a full suite of more user-friendly audio tools, I don't know why you wouldn’t choose that instead.