Convert MP3 to M4R and install it
In short: To turn an MP3 into an iPhone ringtone, open it in RingtoneEditor, choose up to 30 seconds and tap iPhone. The editor encodes the sound as AAC inside an MP4 container, which is what an M4R file is. Renaming .mp3 to .m4r converts nothing, because the audio inside stays MP3. Your file is never uploaded.
Convert your MP3 to a real M4R
Step by step
- Open the MP3 from Files with “Choose a song or video”.
- Drag the handles to the section you want, or start from Chorus, Loudest or First 30 s.
- Use Fade and Louder if the clip needs them, then press Play to hear the result.
- Tap iPhone. The editor encodes your selection as AAC and writes an M4R file.
- Tap Save the ringtone, then follow the install steps shown for your iOS version.
MP3 and M4R side by side
| MP3 | M4R | |
|---|---|---|
| Audio codec | MP3 | AAC |
| Container | MP3 file | MP4, the same as .m4a with a different extension |
| Used for | Music players and Android ringtones | iPhone ringtones and text tones |
| Length limit as a ringtone | None on Android | 30 seconds on iPhone |
Why renaming does not work
A file extension is a label. Rename song.mp3 to song.m4r and the bytes inside are still MP3 audio. Depending on the route, iOS may refuse the file, or copy it across and never list it.
Some converter sites only do this rename. If a “converted” file is exactly the same size as the MP3 it came from, it was probably not converted.
What a real conversion changes
- The sound is decoded and encoded again as AAC. On a phone speaker the difference is hard to hear.
- The length is capped at 29.95 seconds. AAC packs sound into frames of 1,024 samples, and a full 30.00 seconds would spill just past the limit.
- Your MP3 is left as it was. The M4R is a new file, made on your device.
Common questions
Can I convert MP3 to M4R without a computer?
Yes. The editor runs in Safari or Chrome on the iPhone itself, and on iOS 26 you install the result from the Files app.
Is M4R the same as M4A?
The audio inside is the same kind: AAC in an MP4 container. The .m4r extension marks the file as a ringtone.
Can I convert the whole song?
Not for iPhone. A ringtone must be 30 seconds or less, so the editor keeps the part you choose. For Android, tap Android to save an MP3 instead.
Is my MP3 uploaded?
No. Decoding and encoding both happen in your browser, and the file never leaves your device.