Convert AVI videos to MP4.
Turn old AVI files into modern MP4 that plays on any phone, browser and social app — usually at a smaller size. Converted with a local engine, private, and auto-deleted after 1 hour.
Why move off AVI
AVI is a Microsoft container from the 1990s. It still plays on a desktop with the right codecs, but phones, browsers and social platforms increasingly don't accept it — and the files are often big for what they hold. MP4 with H.264 video and AAC audio is the format everything understands today, from an iPhone to YouTube, usually at a smaller size.
It's a re-encode — and that's fine
Because AVI and MP4 use different codecs, the video is re-encoded rather than just rewrapped. We use strong H.264 settings so the result is visually faithful, and the modern codec is efficient enough that you typically get a smaller file at the same perceived quality. Keep the original AVI if you want a pristine archive copy.
Private and local
The conversion runs with a local ffmpeg engine on a private server and the file auto-deletes within an hour — it never goes to a third-party converter.
How it works
- 01
Upload your AVI
Drop a file or pick one from your device. Private by default.
- 02
Convert with a local engine
AVI is re-encoded to MP4 (H.264/AAC) with ffmpeg — no paid API in the loop.
- 03
Download
Grab your MP4, ready to share or upload.
Plays everywhere — iPhone, Android, browsers, social apps
Modern H.264/AAC encoding, usually smaller than the AVI
Private uploads, auto-deleted after 1 hour
No watermark, no signup to try
Handles large files
AVI to MP4: transcode
AVI and MP4 are container/codec formats, so this re-encodes the video (a lossy step — start from the best source you have). MP4 is broadly compatible, which helps when a player, editor or site won't accept AVI.
Your file is ready. Want to do more with it?
Open this file in TranscriptAI to generate a transcript, summary, structured notes, flashcards, quiz questions or action items — automatically.
Common questions
Is it free?+
Yes — convert AVI to MP4 free. Paid plans add larger files, batch and priority.
Is my file private?+
Your file is uploaded to a private bucket, converted, and auto-deleted after 1 hour — never sent to a third-party converter.
Will the quality drop?+
AVI and MP4 use different codecs, so this is a re-encode. We use high-quality H.264 settings, so the change is hard to notice — and MP4's modern codec often looks as good at a smaller size.
Why is my AVI so large?+
AVI is an old container often paired with lightly-compressed codecs. Re-encoding to H.264 in an MP4 usually shrinks the file substantially with no visible quality loss.
Related conversions