convert webm to mp4 online code example

Example 1: ffmpeg webm to mp4

ffmpeg -i "01 - file.webm" -crf 23 "file.mp4"

Example 2: ffmpeg mp4 to webm

# lower -crf value = higher quality & larger output
ffmpeg -i input.mp4 -c:v libvpx-vp9 -crf 30 -b:v 0 -b:a 128k -c:a libvorbis output.webm