AMR File Format (.amr)
An AMR file holds speech compressed with Adaptive Multi-Rate, the narrowband codec 3GPP standardized in 1999 for GSM phone calls, which is why voice memos and MMS voice messages recorded on older phones end up in this format.
AMR at a glance#
| Full name | Adaptive Multi-Rate |
|---|---|
| File extension | .amr |
| Category | Audio Files |
| Developer | 3GPP |
| First released | 1999 |
| MIME types | audio/amr |
| Other extensions | .3ga |
| Compression | Lossy |
| Specification | 3GPP TS 26.090 |
| FileFlip support | FileFlip reads this format but does not write it |
What a .amr file can hold#
These are the things a AMR file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.
| Streaming | Yes |
|---|
Strengths and limitations of AMR#
What AMR does well
- Bit rate adapts in real time between 4.75 and 12.2 kbit/s to match the cellular link, which is what let calls keep working as signal strength changed
- Encodes speech at a fraction of the bitrate an MP3 would need, since it only models the frequency range of the human voice
Where AMR falls short
- Restricted to the 200-3400 Hz band a phone call uses, so music and anything outside speech frequencies sounds thin and muffled
- Most desktop media players and video editors do not recognize it without VLC or an FFmpeg-based converter
- Once recorded, converting to a wider format cannot recover the frequencies AMR never captured
There is rarely a reason to keep audio as AMR once it is off the phone that made it, since the format exists for the transmission link, not for storage.
Convert AMR to MP3 or WAV so an old voice memo or MMS recording opens in ordinary media players and editing software, keeping in mind the recording will still sound like a phone call because that ceiling was set at capture, not by the format.
How to open a .amr file#
A .amr file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts AMR into a format your machine already opens, and it does it in the browser tab rather than on a server.
| Platform | Programs that open it |
|---|---|
| Windows | VLC |
| iOS | VLC |
| Android | Google Recorder, VLC |
| Web | FileFlip |
AMR questions people ask#
Why are my voice memos and MMS recordings AMR files?
AMR is the speech codec GSM and 3G phones use for voice calls, so many phones' voice recorder apps and MMS voice messages reused the same codec rather than encoding a separate format. That link to phone-call audio is also why AMR recordings sound like a phone call, thin and narrowband, rather than like a full-range voice recording.
What plays AMR files?
VLC plays AMR files on every major platform, and Android's own voice recorder and messaging apps read them natively since AMR originated on that ecosystem. Standard desktop media players such as Windows Media Player or QuickTime generally do not.
What should I convert AMR to?
Convert AMR to MP3 or WAV so the recording opens in any media player or editor. Converting will not improve the sound, since AMR only ever captured the narrow speech frequency range a phone call uses, and no conversion can add back detail the codec discarded at recording time.
Converting AMR files#
Convert AMR to another format
FileFlip does not write .amr files, so nothing on the site converts into this format. It works as a source only.
Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.