Quick definition
AVI is an older Microsoft video container that can store audio and video but is less web-friendly than MP4.
Best use cases
Legacy video archives, older Windows recordings, and files created by older capture or editing software.
What to watch out for
AVI files can be large and may fail in mobile apps, web upload forms, or modern browser playback.
Related converters
Conversion tip
Keep the original file, create a converted copy, then compare file size, quality, and compatibility before deleting or uploading the result.