How to use any MP3 file as a free iPhone ringtone
A few weeks ago I showed you how to create your own customized ringtones for the iPhone using a handy software tool called ToneShop. But I recently discovered a very simple trick that enables you to convert your favorite MP3 into an iPhone ringtone right from the iTunes interface, without any third-party apps.
Launch iTunes and choose any MP3 you like. As the maximum ringtone length supported by the iPhone is 30 seconds, you’ll have to trim it a bit (don’t worry, this trimming doesn’t change your original song and can be reverted at any time). Right click on the file, select Get info and click on the Options tab. Insert the file’s start and stop time and click on OK.
Now go back to your Library, right click on your chosen MP3 and select Convert selection to AAC. You’ll get an AAC file with exactly the same name under the highlighted file. Open a File Explorer window and browse to your iTunes music folder (usually C:\Documents and Settings\username\My documents\My music\iTunes\iTunes Music). Locate the song you just converted, which will appear now as an M4A file, and change the extension to M4R.
As soon as you change the file’s extension, it’ll appear as an iTunes ringtone that you can import into iTunes straight away with just a double click. The new ringtone will be show up on the iTunes interface, ready to be synced to your iPhone.
Posted at 8:24 am on Sep 18th
Many thanks for the very good work.
Posted at 9:28 am on Oct 5th
how to convert m4a to m4r. how to change the extension.
Posted at 8:37 am on Oct 6th
Vic, to change the file’s extension you need to right click on the file and select the “Rename” command. The file’s name will then become an active field where you can write the new extension. Press Enter and you’re done
But if you don’t see any extension at all, do the following: open any File Explorer window and go to Tools > Folder Options. Then click on the View tab and uncheck “Hide extensions for known file types”. Windows has this option enabled by default and that can make file renaming a bit confusing.
Posted at 6:23 am on Oct 7th
Elena, thank you so much for replying. I unchecked the “hide extension” and it WORKS !!! Appreciate it.
wooohooo … guess i will be busy converting ringtone for the next few days 
Posted at 9:37 pm on Nov 20th
thanks much , this helped me solving the problem of having my songs as ringing tones on my iphone