AAC to M4R converter
Turn AAC files into M4R for free. The conversion runs entirely in your browser, so your audios are never uploaded anywhere.
How to convert AAC to M4R
- Add your AAC files. Drop one or more .aac files on the box above, or tap it to pick them from your device.
- Let it convert. The first audio you convert loads the converter once (about 31 MB, then cached). After that it runs on your device; a progress bar shows how far along it is.
- Download the M4R. Press Download next to each file. Nothing was sent to a server, so close the tab and it's gone.
What is a AAC file?
AAC is the audio codec used by YouTube, iTunes and most video. Raw .aac files often come out of recorders and downloads.
What is M4R?
M4R is the iPhone ringtone format: AAC audio in an MP4 container with a different name. iPhones only accept ringtones as M4R, and only up to 40 seconds.
Why convert AAC to M4R?
AAC is great for good sound at small sizes, but raw .aac files won't play in many apps, players and cars. M4R is the better choice for iPhone ringtones and alert sounds; keep in mind it only works as a ringtone on Apple devices, and anything over 40 seconds is cut.
Will I lose quality?
M4R uses lossy compression tuned so the difference is invisible to the ear at normal use. We use high-quality settings by default.
Private by design
Most online converters upload your file to their servers. This one doesn't: the converter itself is loaded into your browser and works offline from there, so your audios never leave your phone or computer.
Questions
Is this AAC to M4R converter free?
Yes, completely free, with no sign-up, no watermark and no daily limit.
Are my AAC files uploaded?
No. The conversion happens inside your browser on your own device. Nothing is sent to us or anyone else.
Can I convert AAC to M4R on iPhone or Android?
Yes, in a modern browser. Phones are slower than computers for video, and very long videos can run out of memory on older phones.
Can I convert several files at once?
Yes. Drop as many as you like; they are converted one after another and each gets its own download button.
Is there a file size limit?
No fixed limit, but your browser has to hold the whole file in memory, so files over about 2 GB may fail.