What is AMR (Adaptive Multi-Rate)?
Complete guide to the AMR file format
What is it?
AMR (Adaptive Multi-Rate) is an audio format specifically designed for mobile phone voice recordings. It provides excellent speech compression at very low bit rates (4.75-12.2kbps).
AMR was developed as the standard codec for GSM mobile phone networks and is still widely used for voice memos and recordings on Android phones and WhatsApp voice messages.
Technical Specifications
Pros & Cons
Advantages
AMR files are extremely small - a 1-minute recording is only 50-90KB.
Excellent quality for voice recordings at extremely low bit rates.
Universal support on Android phones and messaging apps.
Low computational requirements save battery on mobile devices.
Disadvantages
AMR is terrible for music - it is optimized only for human speech frequencies.
AMR cannot be played on most desktop media players without codecs.
Any music recorded in AMR will sound extremely poor.
iPhones use M4A for voice recordings instead of AMR.
When to Use It
Here are the most common situations where AMR (Adaptive Multi-Rate) is the right choice:
WhatsApp Voice Notes
WhatsApp voice messages are stored as AMR files on Android devices.
Android Voice Memos
Many Android devices save voice memos as AMR files.
Low-Bandwidth Voice
AMR is used in situations where voice must be transmitted over very low bandwidth connections.
Embedded Systems
IoT devices and embedded systems use AMR for voice recording due to low resource requirements.
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Start Converting NowFrequently Asked Questions
Can I play AMR files on my computer?
VLC media player can play AMR files. Windows Media Player and iTunes do not support AMR by default.
How do I convert AMR to MP3?
Use our free online converter to convert AMR to MP3 for universal playback.
Why did WhatsApp send me an AMR file?
WhatsApp voice messages sent from Android devices use AMR format. Use VLC to play them.
Is AMR good for music?
No, AMR is designed only for voice. It sounds terrible for music due to very low bit rates.
Can iPhone play AMR?
iOS does not natively support AMR. Third-party apps like VLC can play AMR files on iPhone.