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Need help?M4R to AAC Converter
An M4R ringtone already contains AAC audio (AAC-LC), wrapped in an MPEG-4 container with the .m4r extension iPhone uses for tones. This page writes the audio as a bare .aac file instead: an ADTS stream, where AAC frames follow one another, each with its own small header, and there is no MPEG-4 container around them. The codec stays the same, but the conversion is not a simple copy. xconvert decodes the ringtone and encodes it to AAC again, which is what lets you change the bitrate, channels, sample rate and length on the way. Files are uploaded over TLS, processed on xconvert's servers and deleted automatically after a few hours. Free, no sign-up, no watermark, batch friendly.
How to Convert M4R to AAC
- Upload your M4R: Drag one or more
.m4rfiles onto the page or click the upload button. - Set the bitrate: Audio Codec is AAC on this page. Under File Compression pick a Quality Preset (Highest down to Lowest), a Constant Bitrate from 8 to 384 kbps, one of five AAC Variable Bitrate bands (20k-32k up to 96k-112k), a Custom Bitrate in kbps, or a specific target file size. For the cleanest result, stay at or above the ringtone's own bitrate.
- Channel, sample rate and trim (optional): Audio Channel offers Original, Mono or Stereo, and Audio Sample Rate offers Original or 8000 to 48000 Hz. Trim keeps a section defined by a start time and a duration.
- Convert and download: Click Convert and download the
.aacfile from its card, which also lists the values used.
Why Output a Bare .aac File?
- Tools that ask for
.aacby name. Some broadcast and streaming encoders, soundboard apps, web upload forms and older portable players list.aacas an accepted type but not.m4r. - Robust streaming and cutting. Because every ADTS frame describes itself, a partly downloaded or cut-off
.aacfile still plays up to the break. An MPEG-4 file depends on its index being intact. - Android playback. Android's media framework plays raw ADTS AAC, so the file works in Android players without any container questions.
- A neutral file for further processing. Some audio pipelines prefer the raw stream and add their own container later.
If none of these apply, an MPEG-4 file is usually the more convenient result: M4R to M4A keeps the same AAC codec with tags and cover art support.
M4R vs AAC (.aac) — Format Comparison
| Property | M4R | AAC (.aac, ADTS) |
|---|---|---|
| Audio codec | AAC-LC | AAC |
| Container | MPEG-4 | None; a header on every frame |
| Tags and cover art | MPEG-4 tags and artwork | No cover art; limited tag support |
| Duration and seeking | Exact, from the container index | Estimated by players; seeking can be less precise |
| Cut-off or partial file | May not play | Plays up to the break |
| iPhone ringtone | Yes | No |
| Typical use | iPhone ringtones and alert tones | Raw streams, tools that want .aac |
AAC Variable Bitrate Bands and 30-Second Sizes
Lossy size follows bitrate: kbps × seconds ÷ 8 = kilobytes. The five AAC Variable Bitrate bands on this page give these sizes for a 30-second tone:
| Variable Bitrate band | 30-second file | Fits |
|---|---|---|
| 20k-32k | ~75-120 KB | Short beeps and voice alerts, ideally in mono |
| 32k-40k | ~120-150 KB | Speech and simple tones |
| 48k-56k | ~180-210 KB | Voice with light music |
| 64k-72k | ~240-270 KB | Music heard on a phone speaker |
| 96k-112k | ~360-420 KB | Music ringtones in stereo |
If the ringtone was encoded at a higher bitrate than these bands, use Constant Bitrate instead: 128 kbps gives about 480 KB for 30 seconds, and 256 kbps about 960 KB.
Frequently Asked Questions
Are M4R and AAC the same thing?
They share the codec, not the file layout. AAC is the audio codec; M4R is an MPEG-4 container holding AAC with an extension that marks it as an iPhone ringtone. A .aac file is the same kind of audio without the container, written as an ADTS stream.
Will converting M4R to AAC lose quality?
Slightly, because this page re-encodes: the AAC is decoded and encoded again, and every lossy encode discards a little detail. At or above the ringtone's original bitrate the difference is very hard to hear. A higher bitrate than the source does not add detail back.
Can I use the .aac file as an iPhone ringtone?
No. iPhone lists custom ringtones from .m4r files. To go back, AAC to M4R wraps AAC audio in an M4R and shows a note under Trim's Duration about Apple's 30-second ringtone length.
Why is there no album art in the .aac file?
A raw ADTS stream has no container to store artwork in, and tag support is limited. If you need cover art and full tags, keep the audio in an MPEG-4 file such as M4A.
Can Android use a .aac file as a ringtone?
Android plays raw AAC, and many phones let you pick any audio file from storage as a ringtone, but support in the ringtone picker varies by manufacturer. MP3 or OGG is the safer choice when the goal is an Android ringtone; the M4R converter offers both.
Can I convert part of the ringtone only?
Yes. Use Trim with a start time and a duration, in seconds or HH:MM:SS.sss, and only that section is encoded.
Which sample rate and channels should I pick?
Original keeps the ringtone as it is and is the natural choice. Pick 44100 or 48000 Hz only if a tool needs a specific rate, and Mono if you want a smaller file at a lower bitrate and the tone does not depend on stereo.
What happens to my files?
They are uploaded over TLS (HTTPS), converted on xconvert's servers and deleted automatically after a few hours. Protected (DRM) files cannot be converted.