The size of the resulting mp3 audio files is usually equal to or slightly less than the sum of the input mp3 file sizes. This mp3 joiner is absolutely free to use. It is very fast when joining compared to most mp3 joiner software. Mp3 joiner is very easy to use and has a five step guide for the user. The first step requires the user to input an mp3 file into mp3 joiner. This stage has a browse button which lets you select a file using windows explorer from your audio collection. The second step of mp3 joiner is for the user to select another mp3 file to join with the first mp3 file. The third step is for the user to input a name for the mp3 to be output after joining. The fourth step has a join button which launches the joining process displayed in time by a progress bar. The last step of mp3 joiner has a button to open the location of the output file.