Free online M2TS to M4A converter

Source format: M2TS

M2TS is a video container format used mainly for Blu-ray Disc video and some AVCHD camcorders. It typically stores high-definition video, multiple audio tracks, subtitles, and metadata in a transport-stream-based structure. People usually encounter M2TS files when copying footage from a camera, ripping a Blu-ray disc, or working with broadcast-style video recordings.

Because M2TS is primarily a video container, converting it to M4A usually means extracting the audio track and saving it as a standalone audio file.

Target format: M4A

M4A is an audio-only file format in the MPEG-4 family. It commonly contains AAC audio, though it can also store other audio codecs. M4A is widely supported by phones, media players, and editing software, and it is popular because it offers good sound quality at relatively small file sizes.

M4A is a good choice when you want to keep the audio from a video file for listening, editing, transcription, or archiving without the video stream.

How to perform the conversion

The most reliable method is to use FFmpeg, which can extract audio directly from M2TS files without re-encoding if the source audio codec is already compatible, or convert it to AAC for a standard M4A file.

1. Install FFmpeg
Download and install FFmpeg for your operating system, then make sure ffmpeg is available in your command line.

2. Extract audio to M4A
Use a command like this:

ffmpeg -i input.m2ts -vn -c:a aac output.m4a

This tells FFmpeg to open input.m2ts, ignore the video stream with -vn, encode the audio as AAC, and save it as output.m4a.

3. Optional: copy compatible audio without re-encoding
If the audio stream is already AAC and you want to preserve it exactly, you can try:

ffmpeg -i input.m2ts -vn -c:a copy output.m4a

This is faster and avoids quality loss, but it only works when the audio codec is compatible with the M4A container.

4. Convert online on 101convert.com
You can also convert the file on 101convert.com for free, without installing any software.

If you prefer a graphical interface, VLC, HandBrake, or Audacity can help in some workflows, but FFmpeg is usually the best tool for a direct M2TS to M4A conversion.

Notes on quality, compatibility, or limitations

M2TS often contains multiple audio tracks, so make sure you select the correct one if the file has more than one language or commentary track. FFmpeg may choose the default stream automatically, but you can specify a track explicitly if needed.

Because M4A is audio-only, all video and subtitles are discarded. If your goal is to keep the full movie or clip, M4A is not the right target format.

If the source audio is already compressed, re-encoding to AAC can slightly reduce quality. For best results, use stream copy when the codec is compatible, or choose a higher AAC bitrate if you need a fresh encode.

Some M2TS files from Blu-ray discs may be protected or split across multiple segments, which can complicate extraction. In those cases, you may need to work with the decrypted or merged source first.