Drop an .mkv and it is rebuilt as a standard MP4 on your device — plays on phones, TVs, and editors.
Drop an .mkv and it is rebuilt as a standard MP4 on your device — plays on phones, TVs, and editors.
Convert MKV to MP4 in your browser. MKV is a container beloved by recording software and archival tools — and rejected by phones, TVs, editors, and virtually every upload form. GhostVideo re-encodes the file to a standard MP4 (H.264 + AAC) on your device: no upload, no signup, no desktop converter bundled with a toolbar. Because the conversion is local, an OBS recording of a private call stays private.
Drop your MKV
Drag in the .mkv — an OBS recording, a capture, an archive. Convert to MP4 is pre-selected in the GhostVideo studio.
It re-encodes locally
ffmpeg rebuilds the video as H.264 + AAC in a streamable MP4, entirely in your browser.
Download the MP4
Save it — it now plays on phones, TVs, and editors, and uploads anywhere.
Is my file uploaded?
No — the conversion runs in your browser via WebAssembly ffmpeg. Nothing is sent anywhere.
Why does everything reject MKV?
MKV is a flexible container that can hold almost any codec — which is exactly why consumer devices and platforms don't commit to supporting it. MP4 + H.264 + AAC is the compatibility baseline.
Does it keep multiple audio tracks or subtitles?
The primary audio track is converted; extra tracks and soft subtitles aren't carried over. For a quick compatible copy of the main content, that's usually what you want.
OBS gave me an MKV — is that normal?
Yes — OBS records to MKV by default because it survives crashes. Converting to MP4 afterwards is the standard workflow, and now it doesn't need a desktop tool.
Will the quality drop?
The re-encode targets visually-near-source quality. Chain Compress in the same studio if you want a smaller file too.
Every GhostVideo tool runs entirely in your browser. Your file is never uploaded — there's no upload endpoint to send it to.