Free online MPG to WEBM converter

Some browsers, web players, and publishing systems reject older MPG files or handle them inconsistently, while WEBM is accepted directly by many HTML5 workflows. Converting is also useful when web delivery requires a smaller file or modern VP9 or AV1 compression.

What the MPG format is

MPG is a filename extension commonly used for MPEG-1 or MPEG-2 video, often stored in an MPEG Program Stream container. MPEG-1 is associated with Video CD-era media; MPEG-2 is common in DVDs, television recordings, older camcorders, capture devices, and legacy editing systems.

An MPG file may contain MPEG-1 Layer II (MP2), MP3, or other older audio streams. The format remains widely readable, but MPEG-1 and MPEG-2 generally require more bitrate than newer web codecs for comparable visual quality.

What the WEBM format is

WEBM is a Matroska-based container designed primarily for web video. Standard WebM files can contain VP8, VP9, or AV1 video and Vorbis or Opus audio. Current Chrome, Edge, Firefox, and Safari versions support WebM, although support varies by operating system, codec, and device.

VP9 and AV1 usually provide better compression than MPEG-1 or MPEG-2. AV1 can produce smaller files at similar quality, but it normally encodes more slowly and may be harder for older hardware to decode. WebM is not automatically the most compatible choice for older televisions, editing applications, or hardware players; verify the destination's required container and codecs first.

How to convert MPG to WEBM

For a conversion without installing software, use the free converter on 101convert.com. Select the MPG file, choose WEBM as the output format, start the conversion, and download the resulting file when processing finishes. Uploading sends the source to the service, so check its file-size limits, privacy terms, and retention policy before using confidential footage.

For local processing and detailed control, FFmpeg runs on Windows, macOS, and Linux. Open a terminal in the source-file folder and run:

ffmpeg -i input.mpg -c:v libvpx-vp9 -crf 30 -b:v 0 -c:a libopus -b:a 128k output.webm

Replace input.mpg with the actual filename. This command re-encodes the video as VP9 and audio as Opus. With VP9, a CRF around 28–34 is a practical starting range: lower values increase quality and file size, while higher values reduce both file size and quality. The -b:v 0 option enables quality-based variable-bitrate encoding.

Inspect the source before converting when its scan type, frame rate, or audio streams are unknown:

ffprobe input.mpg

For interlaced DVD or television footage, deinterlace it during encoding:

ffmpeg -i input.mpg -vf yadif -c:v libvpx-vp9 -crf 30 -b:v 0 -c:a libopus -b:a 128k output.webm

To reduce encoding time at the cost of compression efficiency, add -deadline realtime -cpu-used 6 to the FFmpeg command. If the source contains progressive video, do not apply a deinterlacing filter.

Quality and compatibility limits

Changing .mpg to .webm does not convert a file. The video and audio streams must be encoded with codecs supported by the WebM container; MPEG-2 video and MP2 audio generally require re-encoding rather than simple remuxing.

Re-encoding is normally lossy, so retain the original MPG and avoid repeated conversions. Preserve the source resolution unless a smaller delivery file is required. Scaling 1080p footage to 720p can reduce bandwidth, but scaling cannot restore detail missing from a low-resolution source.

Check the converted file's picture, audio synchronization, subtitles, and interlacing before publishing. A destination that accepts WebM may still require a specific codec, frame rate, audio format, or maximum resolution.