MKV → YouTube Shorts
Compress MKV for YouTube Shorts
MKV is the archival container of choice because it holds multiple audio tracks, subtitles, and chapters — but YouTube Shorts' uploader is built around MP4 and will either reject MKV or process it so slowly that scheduled posts miss their window. We repackage to MP4 H.264 with the first (or highest-quality) video and audio track selected, crop/letterbox to 9:16 vertical as needed, and output at 1080×1920. Subtitle tracks baked into MKV don't survive the conversion — YouTube Shorts doesn't support embedded subtitle tracks anyway, only the captions you add through YouTube Studio after upload.
Where do you want to share your video?
How to compress MKV for YouTube Shorts
- 1Drag your .mkv file onto the upload zone above (or browse to it).
- 2YouTube Shorts is already selected — we'll target 500 MB to stay safely under the 4 GB cap.
- 3Optionally trim to a highlight clip or switch to H.265 for 30-50% smaller files at the same quality.
- 4Download the compressed MP4 and share it on YouTube Shorts. Source file auto-deletes from our servers after 1 hour.
What to know about MKV → YouTube Shorts
- Multi-audio MKV: we default to the first audio track; re-upload with single-audio source for exact control.
- Embedded .ass/.srt subtitle tracks don't carry over — add captions in YouTube Studio post-upload.
- MKV from anime rips is often 1080p 10-bit HEVC — we transcode to 8-bit H.264 (YouTube requirement).
- Vertical-shot MKV stays vertical; horizontal MKV gets letterboxed or center-cropped to 9:16.
The compression math
A 3-minute 1080p MKV anime clip with HEVC 10-bit + 2 audio tracks + subs = ~400 MB. Re-container to MP4 H.264 8-bit at 1080×1920 vertical, CRF 23 = ~180 MB. YouTube Shorts uploads in seconds instead of minutes.
About MKV files
MKV (Matroska Video) is an open-source container format that supports virtually any video and audio codec, along with multiple subtitle tracks. It's the preferred format for archiving movies, TV shows, and anime because it preserves everything in a single file. However, MKV files are often very large (1GB or more) and are not accepted by social media platforms, messaging apps, or most mobile devices. CompressYourVideo.com converts MKV to a compressed MP4 that you can share anywhere. During conversion, the tool selects the primary video and audio tracks and compresses them to your target size. Subtitle tracks are not preserved in the compressed output since social platforms don't support embedded subtitles.
About YouTube Shorts
Compress and format videos for YouTube Shorts. Shorts require 9:16 vertical format, up to 3 minutes, and look best at 1080×1920. Our tool crops, compresses, and outputs the right specs.
Related compression tools
Or compress MKV for a different platform