Reference

MPEG (.mpg)

MPEG (.mpg/.mpeg) refers to early video formats from the Moving Picture Experts Group — chiefly MPEG-1 and MPEG-2. MPEG-2 powered DVDs and digital TV; the .mpg files you find today are usually older, larger clips by modern standards.

Files & formatsGeneral

MPEG (.mpg)

Also known as: .mpg file, .mpeg file, MPEG-1, MPEG-2, how to open mpg

Early MPEG-1 / MPEG-2 video formats
MPEG-2 powered DVDs and digital TV
Older compression; larger than modern MP4

A family of standards

MPEG names both the standards body and a series of formats. MPEG-1 was an early digital-video standard (the basis of the MP3 audio layer), while MPEG-2 became the format of DVDs, digital cable, and broadcast TV. Later standards like MPEG-4 led to MP4 and the H.264/HEVC codecs.

A plain .mpg or .mpeg file is typically MPEG-1 or MPEG-2 video. These play in VLC and most media players, but they use older compression than today’s formats.

The storage angle

MPEG-1 and MPEG-2 are far less efficient than modern codecs, so an old .mpg often takes much more space than the same footage encoded as MP4 with H.264 or HEVC. Converting legacy .mpg clips to MP4 usually shrinks them substantially.

If you have ripped DVDs or old camcorder files as .mpg, transcoding to a modern format is a common way to free up storage without losing the video.

Related terms

Keep reading the reference.

Files & formatsMP4MP4 (MPEG-4 Part 14) is the most common video container format. The .mp4 file holds video, audio, and subtitle streams together, but does not itself define quality — the codec inside (usually H.264 or HEVC) decides how large and how compressed the video is.General Storage conceptsVideo codec (H.264 vs H.265/HEVC)A video codec is the method used to compress and decompress video. H.265 (HEVC) is the newer successor to H.264 (AVC) and encodes the same quality in noticeably less space, which is why modern phones record in HEVC to keep video files smaller.General Files & formatsContainer formatA container format is the file wrapper that packages compressed video, audio, subtitles, and metadata into one file — for example MP4, MOV, or MKV. It defines how the parts are stored together, not how they are compressed; the codec inside does that.General Storage conceptsCompression (lossy vs lossless)Compression shrinks a file by encoding its data more efficiently. Lossless compression rebuilds the original exactly, while lossy compression permanently discards detail the eye or ear is least likely to notice in exchange for much smaller files.General

Act on it

Guides and tools for this topic.

Compress and resize video