Convert MP4 to MKV
MP4 with H.264 plays on practically every phone, browser, TV and social network. MKV is a flexible container popular for films and screen recordings, but many phones, editors and social sites refuse it. Upload the file, choose MKV and download the result — nothing to install.
Drop a file hereor click to choose one — it opens in the studio with this tool ready. Small files need no account.Choose a fileHow it works
- 1Upload your MP4 file.
- 2Open the video converter and choose MKV as the format.
- 3Download the MKV file.
What you get
Codec control
H.264, H.265 or VP9 for video, AAC, MP3 or Opus for audio — or copy a stream as it is, which is fast and lossless when MKV supports it.
Large files over the API
Files above 100 MB go straight to storage through a signed upload URL, then into the same conversion.
Same result in your code
What you run here is one multipart request over the API, with a webhook when the job is done.
Pay for processing time
One tariff for every operation, capped per file. A failed job is refunded automatically.
Same thing over the API
One header, one multipart request with the file, then poll the job or take a webhook. The same operation you just tried in the browser.
Questions
Will converting MP4 to MKV lose quality?
Re-encoding always changes the data a little; the default settings keep it visually close. If the codecs inside your MP4 are allowed in MKV, choose “copy” to change only the container — nothing is re-encoded.
Is there a size or length limit?
Limits depend on your plan and are listed on the pricing page. A video that is too long is refused up front rather than cut off, and a refused file costs nothing.
Do I need an account?
Small files can be converted without signing up. An account adds a daily free allowance and an API key.
Can I automate it?
Yes. Send the file to the API with service “clipconvert” and operation “convert”, set the format to mkv, then poll the job or take a webhook.