Free online FLV to M2T converter

What the FLV format is

FLV, or Flash Video, is a container created for Adobe Flash-based web video. Older streaming platforms, screen-recording tools, and Flash-era video editors commonly produced FLV files containing H.264, VP6, or Sorenson Spark video and AAC or MP3 audio. Modern players may not open FLV reliably, but FFmpeg, VLC, and many desktop video editors can read it.

What the M2T format is

M2T is a filename extension commonly used for an MPEG-2 transport stream, especially footage recorded by HDV camcorders. It is suited to transport over broadcast-style systems and frame-accurate editing workflows because it stores packetized video and audio streams with timing information.

Typical HDV M2T material uses MPEG-2 video, MPEG-1 Layer II audio, and a fixed transport-stream bitrate. Some software also uses .m2t for transport streams containing other codecs, so the required video codec, resolution, frame rate, audio format, and bitrate should be confirmed before conversion.

How to actually convert FLV to M2T

Using FFmpeg

FFmpeg is the most controllable desktop option. Install a current FFmpeg build, open a terminal in the folder containing the source file, and inspect the streams first:

ffprobe input.flv

For a broadly compatible MPEG-2 transport stream, encode the video as MPEG-2 and the audio as MP2:

ffmpeg -i input.flv -c:v mpeg2video -b:v 25M -maxrate 25M -minrate 25M -bufsize 17825792 -pix_fmt yuv422p -c:a mp2 -b:a 384k -ar 48000 -f mpegts output.m2t

For standard HDV-style 1440×1080 interlaced output at 50 fields per second, use settings matching the source or the receiving device:

ffmpeg -i input.flv -vf "scale=1440:1080,format=yuv420p,interlace" -r 25 -c:v mpeg2video -b:v 25M -minrate 25M -maxrate 25M -bufsize 17825792 -flags +ildct+ilme -top 1 -c:a mp2 -b:a 384k -ar 48000 -f mpegts output.m2t

For 60-field workflows, use the required field rate and field order instead of copying the example blindly. A progressive FLV should not be interlaced unless the target workflow specifically requires it.

Using a desktop video editor

Import the FLV, place it on a timeline, and choose an MPEG-2 transport-stream export preset through a path such as File → Export → MPEG-2 Transport Stream. Set the filename extension to .m2t only when the application actually writes a transport stream; renaming an unrelated MP4 or MPEG program stream does not convert it.

Using the online converter

You can convert the file for free on the 101convert.com website without installing software. Check the resulting stream with a media player or ffprobe before using it in an HDV workflow.

Quality, compatibility, and limitations

Converting from FLV to M2T does not improve quality. If the FLV already uses H.264 or a low bitrate, MPEG-2 encoding adds another lossy generation; preserve the original FLV when archival quality matters.

Changing the extension is insufficient. A valid M2T file must contain an MPEG transport-stream structure, and HDV hardware may additionally require MPEG-2 video, MP2 audio, 1440×1080 or 1280×720 dimensions, a specific interlaced or progressive mode, and a fixed bitrate.

Use ffprobe output.m2t to verify the container and codecs. If the destination accepts only a particular HDV profile, use its documented preset rather than the generic FFmpeg command, because a playable MPEG-2 transport stream may still be rejected by the device.