Convert AVI to MP4 Free — Online AVI Converter

AVI (Audio Video Interleave) is a legacy format from 1992 that you still encounter in old camcorder recordings, CCTV footage, legacy archives, and downloads from older sources. While AVI served well for decades, it produces large files and has poor compatibility with modern devices and platforms.

MiOffice converts AVI to MP4 directly in your browser. No installation, no upload, no signup. FFmpeg WebAssembly handles the conversion locally on your device.

How to Convert AVI to MP4

1. 1

   Open the AVI to MP4 Converter

   Go to the AVI to MP4 converter.

2. 2

   Select Your AVI Files

   Drag and drop your AVI file(s). Choose quality level (High, Medium, Low).

3. 3

   Download MP4

   Click convert. Your modern, compact MP4 files are ready to use anywhere.

AVI vs MP4: Size and Compatibility

Common AVI Sources

• --Old camcorders: MiniDV and early digital camcorders exported AVI by default.
• --CCTV footage: Many security systems still record in AVI format.
• --Legacy downloads: Older media archives and file-sharing networks used AVI extensively.
• --Screen capture software: Some older screen recorders default to AVI output.

Privacy

CCTV footage and personal camcorder recordings contain sensitive content. MiOffice processes everything locally in your browser -- no server upload, no data collection. Your files never leave your device.