Convert 3GP to AMR — Free Online Converter

Both 3GP and AMR originate from the same GSM mobile ecosystem. The 3GP container wraps video and audio streams together, while the AMR (Adaptive Multi-Rate) format is a standalone audio file containing only the voice-optimized codec operating at 8 kHz with bitrates from 4.75 to 12.2 kbps. Converting 3GP to AMR strips the video track and extracts the AMR audio stream, often as a direct copy without re-encoding, producing the smallest possible voice file.

AMR files are still used in telephony systems, voicemail servers, IVR (Interactive Voice Response) platforms, and embedded devices where bandwidth is extremely limited. A standalone AMR file is far smaller than the 3GP wrapper — removing the video track and container overhead can cut file size by 80-95%. This conversion is also useful when feeding audio to speech recognition systems optimized for AMR input, or when sending audio via MMS on networks that enforce strict size limits.