AMR
Also known as: .amr file, Adaptive Multi-Rate, voice memo format
AMR (Adaptive Multi-Rate) is a lossy audio format optimized for speech, used by older phones for voice recordings, voicemail, and MMS. It compresses voice very aggressively, so files are extremely small — but it sounds poor for music because it is tuned only for the human voice.
- Lossy codec tuned for speech
- Very small files; poor for music
- Common in voicemail and old MMS
Built for voice, not music
AMR is a lossy speech codec. It models the range and patterns of the human voice and discards everything outside that, which lets it pack a voice memo into a tiny file — far smaller than an MP3 of the same recording.
That narrow focus is also its limit: run music or anything rich through AMR and it sounds thin and muffled. It is a voice format, full stop.
Where you find it and converting
AMR shows up in voicemail exports, old MMS messages, and recordings from older Android and feature phones. Many modern players and Apple devices do not open `.amr` files directly.
To play or archive an AMR recording reliably, convert it to MP3. The file will grow somewhat but become universally playable.