AVI to MP4 — Convert Online for Free
Convert AVI to MP4 right in your browser: old recordings will open on phones and upload to social media. Nothing is uploaded to a server.
Drag and drop your file here or click to select
About the conversion
AVI is a container from the nineties, and it is where old home recordings, digitised tapes and long-downloaded films still live. The problem is not its age but compatibility: phones normally will not open it, social networks reject it, and it weighs noticeably more than modern formats at the same quality.
MP4 solves both at once — it opens everywhere and it is more compact. When the codec inside already suits the target container, we only swap the container — the wrapper around the video track. That takes seconds even for large clips and, more importantly, leaves the picture untouched: quality stays exactly as it was. Re-encoding kicks in only when there is no way around it, and the tool tells you honestly which of the two paths was used. For AVI it depends on what is inside: old recordings made with DivX or XviD often move across without re-compression.
The file is processed in your browser on your own device and is never uploaded — not to our server, not anywhere else. On the first run the browser downloads the engine once (~32 MB) and takes it from cache afterwards.
Frequently asked questions
How do I convert AVI to MP4 online?
Drag the file into the tool, make sure MP4 is the selected output and start the conversion. The finished file downloads straight away and nothing needs installing.
Will the file get smaller?
Usually yes, especially if the source was compressed with older codecs. The exact difference depends on the contents: where a re-compression-free move is possible, the size stays close to the original and the quality is untouched.
Will the result play on a phone?
Yes. MP4 with H.264 is understood by every modern phone, tablet and TV, and it is accepted by messengers and social networks.
Is the sound preserved?
Yes. If the audio track is in a format MP4 does not accept, it is re-encoded to AAC — the difference is inaudible.
Is the file sent to a server?
No. Everything happens in the browser on your device; the video is never uploaded.