AVI (Audio Video Interleave) is a video container format introduced by Microsoft in 1992 as part of the Video for Windows framework. It was the dominant video format through the 1990s and early 2000s, and AVI files are still common today - particularly from older cameras, camcorders, and downloaded content from that era.
AVI is a container that can hold video and audio encoded with various codecs. Common video codecs found inside AVI files include DivX, Xvid, and older MPEG-4 variants. Unlike modern formats, AVI has limited support for features like chapters, multiple audio tracks, or streaming.
AVI files are often much larger than equivalent MP4 files because they frequently use older, less efficient codecs or store video with minimal compression. Converting an AVI to MP4 with H.264 can reduce file size by 50–80% with no visible quality difference.
MP4 is strictly better than AVI for almost every modern use case. It's smaller, more compatible with current devices and platforms, and supports features AVI does not. AVI's main advantage today is legacy compatibility with older software that may not support newer formats.
AVI is most commonly encountered when working with older footage - video recorded on early digital cameras, archived content from the 2000s, or files sourced from older Windows-based systems.
You can convert AVI to MP4 directly in your browser - no software to install, no upload required. Your file never leaves your device.