Contact

Found a file that will not convert, or need a format we do not support yet? Email us.

1122yukh@gmail.com

What to include in a bug report

• The conversion you tried (for example MKV to MP4) and the quality setting.
• The exact error message shown under the file.
• Your browser and device (for example Chrome on Windows, Safari on iPhone).
• Roughly how large the file is and where it came from (phone camera, screen recorder, download).

Please do not attach private files; the description above is usually enough to reproduce the problem.

Before you write

The conversion failed with an ffmpeg error

The file is probably damaged, DRM-protected, or uses a codec the browser build of ffmpeg does not include. Try another file of the same type to see whether the problem is the file or the format.

It is very slow or the tab crashed

Video conversion runs on a single thread and keeps the whole file in memory. Close other tabs, use a desktop computer for long videos, and keep the tab in the foreground.

The output is larger than the original

That can happen when the source was already heavily compressed. Choose a lower quality setting; the quality guide lists what each one does.