Free online WEBM to 264 converter

Some video tools, hardware decoders, and broadcast workflows require a raw H.264 bitstream instead of a WEBM container. Converting is also useful when a WEBM file must be passed to software that accepts .264 but not VP8 or VP9 video.

What the WEBM format is

WEBM is an open multimedia container usually containing VP8 or VP9 video and Opus or Vorbis audio. Web browsers, OBS Studio, FFmpeg-based screen recorders, video editors, and streaming tools commonly create WEBM files. You may encounter it after downloading browser media, recording a screen or webcam, exporting from a web-focused editor, or saving video from a WebRTC application.

A WEBM file is a container, so its video and audio streams can be inspected independently. Converting it to .264 normally changes the video codec to H.264 and discards audio because a raw H.264 stream has no standard place for an audio track.

What the 264 format is

A .264 file generally contains an elementary H.264/AVC video stream, commonly formatted as an Annex B byte stream. It is used by some decoders, testing tools, embedded devices, broadcast systems, and video-processing pipelines that expect codec data without a container.

H.264 has broader hardware and software support than VP8 or VP9, and it can provide smaller files than older codecs at comparable quality. The raw .264 form is less convenient than MP4 because it normally contains no audio, duration metadata, subtitles, chapters, or thumbnails. Use MP4 with H.264 video when the destination accepts a normal playable video file.

How to actually convert WEBM to 264

Using FFmpeg

FFmpeg is the most direct desktop method. Install a build that includes the libx264 encoder, open a terminal in the folder containing the source file, and run:

ffmpeg -i input.webm -map 0:v:0 -an -c:v libx264 -preset medium -crf 23 -pix_fmt yuv420p -f h264 output.264

This selects the first video stream, removes audio, encodes with H.264, uses a constant-rate-factor quality setting, converts to the widely compatible 8-bit 4:2:0 pixel format, and writes a raw H.264 stream. Replace input.webm and output.264 with the actual filenames.

For higher quality, use a lower CRF such as 18; for a smaller file, use a higher value such as 28. The slow preset usually reduces file size at the same quality but takes longer than medium. If your destination requires a specific frame size or frame rate, add options such as -vf scale=1920:-2 or -r 30.

Using a desktop converter

In a graphical FFmpeg-based converter, add the WEBM file, choose H.264 or AVC as the video codec, disable audio, select a raw H.264 or .264 output profile, set the quality or bitrate, then start the conversion. If the software offers only MP4 as an H.264 output, it is creating a container rather than the raw .264 format.

Converting online

You can convert the file on the 101convert.com website for free without installing software. Select WEBM as the source, choose 264 or H.264 as the output when available, upload the file, and download the converted result.

Quality, compatibility, and limitations

The conversion from VP8 or VP9 to H.264 is a re-encode, so it cannot be completely lossless when the source is already compressed. Keep the original WEBM if it may be needed later, and choose CRF or bitrate based on the required quality and size.

Raw .264 files may not play correctly in ordinary media players because they lack container metadata and audio. If playback, audio, or broad sharing is required, create an H.264 MP4 instead:

ffmpeg -i input.webm -c:v libx264 -preset medium -crf 23 -pix_fmt yuv420p -c:a aac -b:a 128k output.mp4

Some devices require Baseline or Main profile, a maximum level, constant frame rate, or specific dimensions. Add encoder settings such as -profile:v main, -level 4.0, or a scaling filter only when the device documentation specifies them.