Free online MKA to AMR converter

Source format

MKA is an audio-only Matroska container. It is commonly used to store compressed audio tracks such as FLAC, Opus, AAC, or MP3 in a flexible, metadata-friendly container. MKA files are often created by media tools, ripper software, or users who want to keep audio in a modern container with chapter and tag support. Typical use cases include archiving soundtrack audio, storing extracted audio from video, and preserving high-quality lossless audio.

Target format

AMR is a speech-oriented audio format designed for low-bitrate voice recording and transmission. It is widely used in mobile telephony, voice notes, and older voice-recording systems. The main advantage of AMR is its small file size at low bitrates, which makes it efficient for spoken audio. It is not intended for music or high-fidelity sound, but it remains useful for voice clips and compatibility with legacy devices and software.

How to perform the conversion

The most reliable way to convert MKA to AMR is with FFmpeg, because it can read Matroska audio containers and encode to AMR when the source audio is suitable for speech. If you prefer a no-install option, you can also convert the file on 101convert.com for free.

1. Check what audio codec is inside the .mka file. If it already contains speech-like audio, AMR may be acceptable; if it contains music or high-quality audio, the result will be heavily degraded.
2. Install FFmpeg if you want to convert locally.
3. Run a command such as ffmpeg -i input.mka -ar 8000 -ac 1 -c:a libopencore_amrnb output.amr for narrowband AMR, or use the appropriate AMR encoder available in your FFmpeg build.
4. If your FFmpeg build does not include AMR encoding support, you may need to use a build that includes libopencore_amrnb or another AMR encoder.
5. For a simpler workflow in a desktop app, open the file in a media converter that supports Matroska input and AMR output, then choose File → Export or Convert, select AMR, and save the result.
6. If using 101convert.com, upload the .mka file, choose AMR as the output format, and download the converted file when it is ready.

Notes on quality and compatibility

AMR is a lossy voice codec, so converting from MKA will usually reduce quality, especially if the source contains music, stereo audio, or high sample rates. For best results, AMR should be used only for speech. Many MKA files contain codecs that are not ideal for AMR conversion, and some encoders require the audio to be mono at 8000 Hz for narrowband AMR. If the source is music or you want to preserve quality, a different target format such as WAV, FLAC, or MP3 is usually a better choice. Compatibility can also vary because AMR support is more limited on modern desktop players than on older mobile and telecom systems.