Why can't my iPhone play AVI files?

iOS and the Apple ecosystem only support H.264 and HEVC video in MP4 or MOV containers. AVI is not a supported container on iPhone. Converting to MP4 is the fix.

Will converting AVI to MP4 reduce quality?

For most AVI files, re-encoding to H.264 MP4 is done at high quality settings. Some quality reduction is inherent in re-encoding, but the output is excellent for viewing and sharing purposes.

My old AVI videos use the DivX or Xvid codec — will they convert?

Yes. FFmpeg supports DivX 3/4/5, Xvid, and most other classic AVI codecs. These old files typically convert well to H.264 MP4.

Can I upload AVI to YouTube?

YouTube does accept AVI, but MP4 with H.264 is the recommended format for fastest processing and best quality. Converting first often speeds up YouTube processing and avoids codec-related issues.

Are my videos uploaded to a server?

No. FFmpeg.wasm processes everything in your browser.

What's the maximum AVI file size?

100MB per file. Old DV or SD-resolution AVI files are often under this limit; HD AVI files may exceed it.

How long does conversion take?

AVI re-encoding takes longer than a simple re-wrap because the video must be re-encoded. Expect roughly 1–3 seconds per minute of video on a modern computer.

AVI to MP4 Converter

Convert AVI to MP4 free online — no upload, no signup. Play old AVI videos on iPhone, Android & modern apps. Browser-based, 100% private. No quality loss.

FileConvertir — Free Online File Converter