AVI is an old format many phones, browsers and editors no longer play. MP4 works everywhere and is usually smaller. This converter runs entirely in your browser — the file is never uploaded.
Why convert AVI to MP4?
AVI is an old format many phones, browsers and editors no longer play. MP4 works everywhere and is usually smaller.
How it works
The video is re-encoded to H.264 with AAC audio in an MP4 container. The conversion runs with ffmpeg compiled to WebAssembly, on your device.
Quality notes
H.264 is far more efficient than the codecs typically inside AVI, so the MP4 is often much smaller at the same quality.
Common use cases
Modernising old camera and archive videos; playing old clips on phones and TVs.
Frequently asked questions
Why is the MP4 smaller?＋
H.264 compresses much better than older AVI codecs.
Does it work with old camcorder AVIs?＋
Most do; very unusual codecs may not decode.
Is my file uploaded?＋
No. The conversion runs in your browser; the file stays on your device.