Files with the file extension M4R are associated with the Apple iPhone ringtone format. The extension accompanies a few other Apple ringtone formats which include M4A and MPEG-4. M4R files are the most widely used for the delivery of ringtones on the Apple iPhone.
M4R files are an audio file type that contains numeric representations, audio files, and text in ASCII format. Since M4R files are associated with M4A files, you can convert the M4A format by changing the extension to M4R. This is especially useful when obtaining ringtones and music created with the M4A file extension from iTunes.
M4R files are custom ringtones which can be created using audio tracks you have purchased from the iTunes store. The audio tracks must also provide the necessary permissions for converting the music into a ringtone. You simply purchase the music track and then transfer it to your iPhone after you sync your device to the iTunes store. The M4R files are then created using any compatible ringtone maker software application.
How to Open M4R Files
To open an M4R file, double click on the file to see if it will automatically open in a default application you have installed on your PC. Since M4R files are an audio file type, you may be able to open them using a program you already have on your computer.
If you use Windows, you can open M4R files with Apple iTunes for Windows. If the M4R file has been converted into a ringtone and is copyright protected, you can open it using VideoLAN VLC Media Player, which is available as a free download from the VideoLAN website. You can also use ImTOO iPhone Ringtone Maker or Tipard iPhone Ringtone Maker to open M4R files in Windows.
For Mac OS X, you can open M4R files using Apple iTunes for Mac, GarageBand, or Apple iOS 5. Other programs that will open M4R files on a Mac system include Aiseesoft iPhone Ringtone Maker for Mac, Ringtone Designer for iPhone, Ringtone Maker for iPhone, or Xilisoft iPhone Ringtone Maker for Mac.
If you use the Linux operating system, M4R files can be opened with VideoLAN VLC Media Player, which is an open source media player that is multiplatform and is available as a free download from the VideoLAN website.
You can also opt to convert the M4R file to another format which makes it usable with a broader range of media applications. Programs such as iRing and M4R Converter are available for download from the CNET website and will help you convert M4R files to another format.