MP4 to MKV Converter (.mp4 to .mkv)

Convert MPEG-4 Part 14 Video Container (.mp4) files to Matroska Multimedia Container (.mkv) directly on your device. MP4 is commonly used for web video streaming, social media uploads, screen recordings, and extracting audio tracks to mp3/wav, while MKV is ideal for remuxing obs studio recordings to mp4 for premiere/davinci resolve or extracting audio tracks. Every conversion runs locally in your browser with zero server uploads.

100% On-Device Processing • Files Never Leave Your Browser (0 KB Uploaded)

Why Convert MP4 to MKV Locally?

Personal videos and internal meeting recordings are processed 100% on your device. Unlike cloud converters that upload your .mp4 files to remote servers, Artoons processes your files directly on your device.

How to Convert MP4 to MKV

  1. Select or drag and drop your .mp4 (MP4) file into the converter above.
  2. Confirm MKV (.mkv) as the target format and choose your preferred quality preset.
  3. Click Convert to automatically download your converted .mkv file.

Frequently Asked Questions

Do my MP4 files ever get uploaded anywhere?

Never — 100% of the conversion runs locally inside your own device memory with 0 KB sent over the network.

Will MP4 to MKV look or sound worse?

Both MP4 and MKV keep crisp detail when swapped locally on your own hardware. You can also tweak output quality in Preferences anytime.

How big of a .mp4 file can I convert here?

Right in this browser tab, you can convert .mp4 files up to 200 MB per file. Pushing bigger clips or giant folders? Grab the free Artoons Desktop App for unlimited sizes.

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