What is an AMR file?
AMR is the audio from old phone recordings and voice messages, squeezed hard enough to fit down a phone call. Speech comes through clearly, music does not. Converting to MP3 makes it play on anything. You can turn an AMR into other formats here, though nothing can be saved back as AMR.
Specification
| Full name | Adaptive Multi-Rate Audio |
|---|---|
| Extensions | .amr |
| Media type | audio/amr |
| Compression | Lossy |
| Transparency | — |
| Animation | — |
| Multiple pages | — |
| Colour depth | 8 kHz narrowband, 4.75 to 12.2 kbps |
| Size limits | — |
| Introduced | 1999 |
| Developed by | 3GPP |
| Standard | Open |
| Browser support | Not displayed by browsers |
What AMR is used for
- Voice recordings from older mobile phones
- Voicemail and call recording archives
- MMS voice attachments
Strengths and limitations
What AMR does well
- Extremely small files for speech
- Designed to degrade gracefully on unreliable networks
Where AMR falls short
- Narrowband and unusable for anything but speech
- Almost no consumer software plays it directly
Convert AMR to
Every target this format can be written out as, each on its own page.
Tools that accept AMR
Questions about AMR
What is a .amr file?
AMR is the audio from old phone recordings and voice messages, squeezed hard enough to fit down a phone call. The extension .amr identifies it, and its media type is audio/amr.
How do I open an AMR file?
Browsers do not display AMR natively, so you either need software that understands it or you convert it to something more common first. Converting is usually the faster route when you only need to look at the contents once.
Is AMR lossy or lossless?
Lossy. That means detail is discarded during encoding and each re-save compounds the loss, so keep an untouched master where quality matters.
What is AMR good for?
Extremely small files for speech. Designed to degrade gracefully on unreliable networks. In practice that makes it a good fit for voice recordings from older mobile phones, and Voicemail and call recording archives.
What are the drawbacks of AMR?
Narrowband and unusable for anything but speech. Almost no consumer software plays it directly.