Free online M2T to OPUS converter

An M2T recording may contain an audio stream alongside MPEG-2 video, while OPUS is audio-only. Convert it when a player, voice application, or archive workflow requires a compact OPUS file instead of the original transport-stream recording.

What the M2T format is

M2T is an MPEG-2 Transport Stream file, commonly produced by HDV camcorders, broadcast capture systems, and video-editing workflows. It usually contains video plus MPEG audio or AC-3 audio, so converting it to OPUS requires extracting the audio stream rather than transcoding the video.

What the OPUS format is

OPUS is a lossy audio codec packaged as an .opus file. It supports speech and music, works well at low bitrates, and is widely supported by modern browsers, media players, messaging applications, and WebRTC-based software. It is suitable when a smaller file is more useful than the source audio's original codec and bitrate.

How to actually convert M2T to OPUS

For desktop conversion, FFmpeg handles transport streams and audio extraction directly:

1. Install FFmpeg and place the M2T file in an accessible folder.
2. Inspect the available streams with ffprobe input.m2t if the file may contain multiple audio tracks.
3. Convert the first audio stream with ffmpeg -i input.m2t -map 0:a:0 -c:a libopus -b:a 128k output.opus.

The -map 0:a:0 option selects the first audio stream and excludes video. Use -map 0:a:1 for a second audio stream. For speech or voice recordings, -b:a 64k is often sufficient; use approximately 96–160 kbps for music, depending on the required quality.

You can also convert the file for free on the 101convert.com website without installing software. Select the M2T input, choose OPUS as the output, start the conversion, and download the resulting audio file.

Quality, compatibility, and limitations

OPUS encoding is lossy: converting an already compressed MPEG or AC-3 stream cannot restore information discarded by the original recording. The output normally uses a 48 kHz sample rate, which matches OPUS's common operating mode; resampling is unnecessary unless a specific application requires another rate.

If FFmpeg reports that no audio stream exists, the M2T file contains video only or uses an unsupported stream. If the source has several language or commentary tracks, inspect ffprobe output and select the intended stream explicitly. Some older players and hardware do not support OPUS, so retain the original M2T when long-term editing or maximum source fidelity is required.