There are scenarios that we need to compress MKV files into smaller files. One of these scenarios is transferring MKV files using Gmail, which has a 25MB size limit. To solve such problem, a video compressor is necessary.
Here I'd like to share 3 tools to compress MKV video files.
1. Free online tool - Vidmore Free Online Video Compressor
This free online video compressor can help you compress MKV in three easy steps, with no sign-up or watermark.
Step 1. Visit https://www.vidmore.com/free-online-video-compressor/ to use this web-based tool. Click "Compress Now" button to download a smaller launcher.
Step 2. After the launcher is downloaded and installed successfully, click the "Compress Now" button again to upload the MKV file you want to compress.
Step 3. You can set the compression rate, output format to convert MKV file format, resolution etc. according to your need. Then click "Compress" button to reduce the MKV file size.

2. HandBrake
HandBrake is an open-source and free video compressor and conversion software.

3. Vidmore Video Converter
This is an all-in-one video processing tool that comes with video converter, video editor, video enhancement, video compressor, GIF maker and more features. You will be amazed by its powerful functions.

Keep reading to learn more details about the 3 MKV compressor introduced above: https://www.vidmore.com/edit-video/compress-mkv/