AMR file format (.amr)
Adaptive Multi-Rate speech codec, used for voice notes.
Last updated
What is an AMR file?
In short: An AMR file (.amr) is an audio file in the AMR format. AMR is tuned entirely for the human voice, at bitrates between 4.75 and 12.2 kbps. It can be converted to MP3, WAV or FLAC for free in a web browser with iHateFiles, without uploading it.
Adaptive Multi-Rate, adopted by 3GPP in 1999 as the speech codec for GSM and 3G phone calls.
AMR is tuned entirely for the human voice, at bitrates between 4.75 and 12.2 kbps. It is what mobile networks carried calls on for two decades, and what phones used for voice memos and MMS.
What AMR is good at
- Intelligible speech at a tiny fraction of music bitrates
- Adapts its rate to network conditions
- Universal on older phones
Where AMR falls short
- Music sounds unmistakably wrong
- Narrow frequency range, roughly telephone quality
- Little support outside phones
When to use AMR
Convert AMR to MP3 or M4A to play a voice memo on a computer.
How to open a AMR file
Phones and VLC.
| Windows | VLC. Windows has no built-in AMR support. |
|---|---|
| macOS | VLC or QuickTime — older versions of QuickTime handled AMR. |
| Linux | VLC or mpv. |
| Phone | Android records voice memos in AMR and plays them natively. |
| In a browser | No browser plays AMR. |
The thing that usually goes wrong
Converting AMR to a high bitrate does not improve it. The frequencies were never recorded.
Questions
What is a AMR file?
Adaptive Multi-Rate speech codec, used for voice notes. Files use the .amr extension.
How do I open a AMR file?
AMR is not widely supported any more. The reliable route is to convert it to a current format, which this page can do in your browser without uploading it.
Can I convert AMR for free?
Yes. Every conversion here is free and unlimited, because your own device does the work rather than a server we have to pay for.
Is AMR lossless?
No. AMR is a lossy format, so saving discards some detail to save space.