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.
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Common questions
Is it free?+
Yes. Convert AVI to MP4 free. No signup, no watermark, no daily cap.
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.
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