Upload M4R file from your device memory or cloud or via URL
Once uploading is complete, press the convert button
Wait until the end of the conversion and download new OGG file
M4A is an audio file compressed using MPEG-4 technology, which has a lossy compression algorithm. The M4R file contains the ringtone in the M4A MPEG-4 file format, which uses the default audio format to store the song in the iPhone. The M4R format, like M4A, is designed to download audio to Apple devices through iTunes. Such a file can be created by converting other formats or uploading it from the official iTunes store. You don't have to look for converters or special programs, you can make m4r from m4a using standard tools of any operating system by changing the last letter of the extension manually. But for this to work like an iPhone ringtone, remember that it can only be created from songs purchased from the iTunes music store.
An OGG file is a compressed audio file that uses the free, proprietary Ogg Vorbis audio compression. Many connoisseurs of modern audio formats consider the Ogg format to be one of the most promising and, in particular, a worthy competitor to popular formats. Basically, it is a multimedia container format standard that is run by the non-profit organization Xiph.Org. Ogg Vorbis has the most modern and high quality psychoacoustic model, which is why the bitrate / quality ratio is significantly better than that of competitors. The OGG format has the main advantage - with the same bitrate, this format gives a higher quality in comparison with other formats. This 320 kbps bitrate format is used in Spotify broadcasts. In addition to the open source code, it should be noted that OGG is multiplatform. The encoder is compatible with almost all available operating systems.