Browser FFmpeg recipe

Convert AVI to MP4 Online with FFmpeg

Create a modern MP4 from an AVI source file.

Command

Run this FFmpeg command

ffmpeg -i input.avi -c:v libx264 -crf 23 -preset fast -c:a aac -b:a 128k output.mp4

When to use it

  • older camera files
  • legacy videos
  • web compatibility

How it works

  1. Upload the AVI file.
  2. Run the MP4 conversion command.
  3. Download the converted MP4.

Option reference

OptionWhat it does
-c:v libx264Encodes AVI video to H.264.
-c:a aacEncodes audio to AAC.
-crf 23Sets a balanced quality level.

Practical notes

  • Some old AVI codecs may not be available in the browser FFmpeg build.
  • Use a higher CRF value if the output is too large.

FAQ

Why convert AVI to MP4?

MP4 is easier to play in browsers, phones, and current editors.

Will this preserve quality?

It re-encodes the video, so use a lower CRF value for higher quality.