Step 1: Supply your MP4 files using the button above or by haul and lay.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Get your converted M4R files.
MP4 to M4R Conversion FAQ
What does the MP4 to M4R converter do?
+
It converts a MP4 file into M4R format.
Will the data inside my MP4 be preserved when converting to M4R?
+
Yes — the content is mapped to the M4R equivalent. Format-specific extras that M4R does not represent natively are omitted rather than corrupted.
Is the MP4 to M4R conversion reversible?
+
You can convert the M4R back to MP4 on this site. If either format involved is lossy, the round-trip is not bit-perfect even though it is visually or audibly close.
What output quality should I expect from MP4 to M4R?
+
Default settings target broadcast / web quality — visually identical to the source for most viewers. For archival use, pick the highest quality option in the converter settings.
Is converting MP4 to M4R a second round of lossy compression?
+
Yes, and it is worth planning around. Both formats are lossy, so the M4R encoder is working from audio that has already been through one psychoacoustic pass, and its own decisions compound the first set. At 192 kbps or above the result is still transparent for most listening. If you have a lossless master anywhere, encoding the M4R from that instead avoids the double pass entirely. Almost every MP4 in the wild is H.264 video with AAC audio; the container also legally holds HEVC, AV1 and VP9. The payload is AAC, conventionally capped at 40 seconds, which is the longest tone iOS will accept.
Can I tag the M4R with artist and album information?
+
Yes, and it is a genuine gain over MP4, which has nowhere dependable to store any of it. M4R carries title, artist, album, year, track number and embedded cover art in the container itself, so a music library files it correctly without a manual pass. M4R drops straight into the iOS Sounds list via Finder or iTunes with no further processing.
What happens to multichannel audio when converting MP4 to M4R?
+
It is folded down to stereo, because M4R has no practical multichannel mode. The downmix uses the standard coefficients so centre-channel dialogue stays clear and the surrounds are mixed in at reduced level. Anything that depended on discrete channel placement is gone once that happens. M4R is Apple-only and length-limited; anything over 40 seconds is silently rejected by the phone.
Is there a file-size limit when converting MP4 to M4R?
+
Anonymous uploads are capped at a generous default; signed-in free accounts get a higher cap, and Pro accounts have no per-file limit. Browser memory is usually the practical constraint long before our server-side limits kick in.
Can I batch-convert several MP4 files to M4R at once?
+
Yes. Drop or pick multiple MP4 files in one upload — the converter processes them in parallel and returns a ZIP of the M4R results. There is no need to repeat the upload step per file.
What happens to my MP4 files after the conversion?
+
Uploaded files and M4R outputs are auto-deleted after a short retention window. We do not inspect, share, or train on user files. Direct download links are time-limited and tied to your session.
Where can I open my M4R file?
+
M4R opens in the standard tools for its category. Browsers and built-in OS viewers handle the common cases.
Do I need to install software to convert MP4 to M4R?
+
No. The converter runs entirely in your browser plus our cloud — no plugin, no install, no admin rights. It works on Windows, macOS, Linux, ChromeOS, iOS, and Android.
