MKV compressor

Compress MKV files in a few clicks and at super speed
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Compress MKV

With our online compression tool it’s easy to compress any MKV file without installing any software. Just import your file in our compression tool, drag the compression settings sliders to choose the level of compression and save the video.

MKV compressor

Reduce MKV file Size

With Flixier it’s easy to reduce the file size of an MKV file. Just import the file in our compressor and move the settings sliders according to your needs. You can prioritize a smaller file size or a higher quality.

Compress MKV online

Flixier runs in your browser meaning that you don’t need to download or install any software. This is great because you don’t need to consume space on your computer with additional software and you don’t need to waste time with downloads or installs.

Fastest MKV file compressor

Flixier processes all your video files in the cloud with a unique technology which will complete your MKV compression at super speed. All without using any of your computer’s resources. You can compress files even on a Chromebook.

Free MKV file compressor

On top of all the features that make Flixier the best MKV file compressor, our tool is also free. This means that you can enjoy fast compression speeds on any device without spending any money.

How to compress MKV online

How to compress MKV online
Add your files to the compressor

First go to the video compressor tool and click the “Upload Your File” button. Now browse the file you want to compress and select it. It will be uploaded to your servers and prepared for compression.

Apply the compression settings

Reduce the MKV file size by lowering the bitrate or CRF level the Frame rate or the resolution. It’s super easy to make these changes with a slider and you will even see the estimated Compressed Size.

Download or edit your video

When ready press the “Compress Video” button. The video will be processed in a couple of minutes. When ready you can download it on your computer or edit with the Flixier video editor to instantly add subtitles, transitions, music directly in your browser.

Why use Flixier to compress MKV files

Make big files easier to share

Compressing MKV files with Flixier makes it easier to share them with your colleagues or family and to store them for the long term.

Compressed files are saved as MP4

When you compress an MKV file with Flixier it will always be saved as an MP4 file, making it compatible with any video player, mobile device or social media platform. This will make it easier for you to share files with anyone on any platform.

Change the resolution of a file

Our video compression tool will also let you change the resolution of a video. You can easily lower down the resolution of a video file to make it smaller in size.

Edit MKV video files

Flixier is so much more than a MKV file compressor. With Flixier you can also edit videos, add subtitles automatically, add music, transitions and so much more, all in a simple interface that runs super fast in your browser.


I’ve been looking for a solution like Flixier for years. Now that my virtual team and I can edit projects together on the cloud with Flixier, it tripled my company’s video output! Super easy to use and unbelievably quick exports.

Steve Mastroianni -

My main criteria for an editor was that the interface is familiar and most importantly that the renders were in the cloud and super fast. Flixier more than delivered in both. I've now been using it daily to edit Facebook videos for my 1M follower page.

Evgeni Kogan

I'm so relieved I found Flixier. I have a YouTube channel with over 700k subscribers and Flixier allows me to collaborate seamlessly with my team, they can work from any device at any time plus, renders are cloud powered and super super fast on any computer.

Anja Winter, Owner, LearnGermanWithAnja

Frequently asked questions.

Frequently Asked Questions

If you have any further questions, Get in touch with our friendly team
If you have any further questions, Get in touch with our friendly team

Am I losing quality when converting a MKV video file?

Am I losing quality when converting a MKV video file?

The quality loss when compressing an MKV file depends a lot on the settings you choose and if you are trying an aggressive compression or not. When reducing the file size by about 30% video quality is minimal but trying a higher compression might be visible in some cases. Still, with most being shared on social media and watched on phones it takes a large amount of compression to make a video look noticeably bad.

Can I reduce the mkv file size using an online video editor?

Can I reduce the mkv file size using an online video editor?

Yes, you can compress the size of an MKV file with an online video editor like Flixier. First make your edits and export your video. Flixier will automatically save it as an MP4 file which usually comes with a smaller file size. Still, if you want to compress files even more head over to our video compressor.

Can I compress MKV files for free with Flixier?

Can I compress MKV files for free with Flixier?

Yes, with Flixier you can compress MKV files for free, just upload them into our compression tool, apply the settings that you want based on how small you want to make the file and press the “Compress video” button. When ready you can download the file or edit it with our online video editor.

Can I compress MKV files for free with Flixier?

Can I compress MKV files for free with Flixier?

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