The first thing that you need to do, before getting started with the process of converting an mp3 into a ringtone, is to ensure that you have a cell-phone that supports mp3 ringtones, an mp3 version of the song that you want to convert into an mp3 ringtone on your computer hard-disk, and a cable to transfer the mp3 ringtone to your cell-phone. If both your computer and cell-phone have the Bluetooth feature, then you can also use this to transfer the ringtone from one device to the other.
If the song that you want to convert into a ringtone is in a format other than mp3, such as FLAC, rip it using a music ripping software, to a WAV or AIFF format. Windows Media Player, Rhapsody and iTunes can be used to rip the music file to the aforementioned format. Save the mp3, WAV or AIFF file in a new folder, so that the original file remains unaffected during the process.
Use an audio editing software to change the bit rate of your music file. You can download free audio editing software or programmes from the Internet. You will also need to download the LAME library. Download it to a separate folder.
Run the audio editing software and access the option to change the bit rate. Change it to 128 kilobytes per second.
Open the LAME library, and find the music file that you want to convert into a ringtone. Open the file using your audio editing software, and select the segment of the song that you want to use as your ringtone. Keep in mind that the segment should be no longer than 15 seconds.
Look for the option “export to MP3” in the file drop-down menu, and save the segment that you selected in the previous step as an mp3 file.
Connect your cell-phone to your computer, using the data cable or via Bluetooth, and transfer the ringtone to your cell-phone.