Step-by-step instructions
- 1
Convert with FFmpeg (fastest, highest quality)
ffmpeg -i input.mp4 -c:v mpeg4 -vtag xvid -c:a libmp3lame -b:a 192k output.avi. This encodes video as MPEG-4/Xvid and audio as MP3 — the most compatible AVI codec combination.
Go to converter - 2
Convert with VLC
VLC → Media → Convert/Save → Add MP4 → click Convert/Save → click Profile wrench icon → choose AVI container → Video Codec: MPEG-4 → Audio Codec: MP3 → Save → set output path with .avi extension → Start.
- 3
Understand AVI limitations
AVI files are larger than MP4 for equivalent quality (Xvid is less efficient than H.264). AVI doesn't support B-frames in some players, which affects quality. If you don't specifically need AVI, MP4 or MKV are always better choices.
Why convert MP4 to AVI?
AVI remains required for certain legacy workflows: DVD authoring software, older video capture hardware, and some editing suites that don't accept MP4. Converting bridges the gap for these specific use cases.
Your files never leave your device
FormatDrop runs the conversion engine entirely inside your browser using WebAssembly. No file upload. No server. Nothing stored. You can verify this by opening DevTools → Network tab and watching: zero upload requests.
Frequently asked questions
Why would I need AVI instead of MP4?
Is AVI quality better than MP4?
No account. No upload. Works in any browser.