Convert MP4 to MKV
Convert MP4 to MKV online for free. Upload your MP4 and get a high-quality MKV in seconds. No install, no watermark, files deleted automatically.
Free online MP4 to MKV converter
Convert MP4 to MKV in a few clicks. Add your MP4 above, and Tool Cloud converts it on our servers and gives you a MKV to download, with no software to install and no watermark.
How to convert MP4 to MKV
- 1
Upload your MP4 file
Click "Select Files" or drag and drop your MP4 into the upload box.
- 2
Adjust the options
Optionally pick quality, size or other settings for your MKV output.
- 3
Download your MKV
Click "Process", wait a few seconds, then download your converted MKV.
About the formats
MP4 is the most compatible video format in the world. It plays on virtually every phone, browser, TV and editing app while keeping file sizes reasonable.
MKV is a flexible open video container that can hold multiple audio tracks and subtitles. It is popular for movies and series, but not every device or editor supports it.
Frequently asked questions
How do I convert MP4 to MKV?
Add your MP4 above, click "Process", and download the MKV when it is ready. It usually takes just a few seconds.
Is the MP4 to MKV converter free?
Yes. Each use costs 6 credits, and everyone gets 20 free credits every day without an account. Sign up to get 50 free credits, or buy a credit pack if you need more.
Will converting MP4 to MKV reduce quality?
Both MP4 and MKV use lossy compression. Tool Cloud converts at a high quality setting by default, so the difference is usually not noticeable.
Are my files safe?
Yes. Your files are only accessible to you, are transferred over an encrypted connection, and are deleted automatically after processing.
Can I convert multiple MP4 files to MKV at once?
Yes. Select several files at once and Tool Cloud converts them all. You can download each MKV when it is ready.
Fast, private and built for real work
Everything runs on our servers, so it works the same on any device.
Lightning fast
Files are processed in seconds by a dedicated worker queue, with live progress while you wait.
High quality output
Professional-grade engines like FFmpeg and Pillow keep your output crisp and faithful.
Secure & private
Uploads are only visible to you and are deleted automatically after processing.
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