Browser FFmpeg recipe
Transcode Video Online with FFmpeg
Create a freshly encoded MP4 from a source video.
Command
Run this FFmpeg command
ffmpeg -i input.webm -c:v libx264 -crf 23 -preset medium -c:a aac -b:a 128k transcoded.mp4When to use it
- codec changes
- compatibility fixes
- standard MP4 output
How it works
- Upload the video file.
- Adjust CRF, preset, or audio bitrate if needed.
- Run FFmpeg and download the transcoded MP4.
Option reference
| Option | What it does |
|---|---|
-c:v libx264 | Encodes video with H.264. |
-preset medium | Balances speed and compression efficiency. |
-c:a aac -b:a 128k | Encodes audio as AAC at 128 kbps. |
Practical notes
- Transcoding can be slower than remuxing because every frame is encoded again.
- Use convert video to MP4 for a faster preset with similar compatibility goals.
FAQ
What is transcoding?
Transcoding decodes media and encodes it again with new codec settings.
When should I transcode instead of copy?
Use transcoding when the target app rejects the original codec or container.