M4R
Perfect and easy to use mp4 to m4r tool
iPhone Ringtone Maker is the most popular mp4 to m4r conversion tool which can convert music purchased from iTunes store to iPhone ringtone, and help you clip any music segment from video/audio file and turn it into iPhone ringtone. Moreover, it supports directly add video files to iPhone. Just follow me to look at this perfect m4r converter!
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1.Free download this powerful m4r software online, run it,
2. Here click "Add File" button to browse MP4 videos you want to convert and add them into the MP4 to M4R Converter.
3. There is editing function. You can drag the two sliders to reset start point and end point to select the only clip of the file you want to set as ringtone.
4. Make sure the Local Folder to save the converted files.
5. Click "Generate" button. This MP4 to M4R Converter will start the conversion and then automatically transfer to your iPhone without iTunes.