Compress MKV Online — Reduce File Size by Up to 40-70%
Compress MKV files online instantly. Reduce .mkv file size by 40-70% with no quality loss. Batch compress 100+ files. No signup, no watermarks.
Batch Settings
About MKV Compression
MKV (Matroska) is the most versatile video container — supporting any codec, multiple audio tracks, subtitles, and chapters. MKV files from Blu-ray rips and high-quality sources can be extremely large.
CocoConvert re-encodes the video stream while preserving all audio tracks, subtitles, and chapter markers. The MKV container itself adds no overhead — it's the video codec and bitrate that determine file size.
For MKV files with H.265/HEVC content, further compression is limited since H.265 is already highly efficient. For H.264 or MPEG-2 content, re-encoding typically achieves 40-70% reduction.
Batch compression handles multiple MKV files simultaneously on Pro plans.
How to Compress MKV
- 1
Upload your MKV file
Drag and drop your .mkv file into the upload area, or click to browse. Batch upload is supported.
- 2
Adjust compression settings
Use the quality slider to control the compression level. Lower values produce smaller files.
- 3
Click "Compress"
CocoConvert compresses your MKV file using optimised video encoding.
- 4
Download the compressed MKV
Your smaller .mkv file is ready. Typical reduction: 40-70%.
Compression Tips
MKV
.mkv file • Video
Use H.264 or H.265 codec for maximum compression ratio.
| Extension | .mkv |
| MIME Type | video/x-matroska |
| Category | Video |
Frequently Asked Questions
What are the limits for MKV compression?
CocoConvert lets you compress MKV files with no signup required. You get 5 files per hour (up to 250 MB each) on the starter tier. Pro users get 100 files per hour and 5 GB per file.
How much can I reduce MKV file size?
Typical MKV compression reduces file size by 40-70%, depending on the original file and quality settings. Tip: CRF 23 for H.264, CRF 28 for H.265.
Does compression affect MKV quality?
CocoConvert gives you full control over the quality-size trade-off. Higher quality settings preserve more detail; lower settings produce smaller files. For lossless formats, compression is always bit-for-bit identical.
Is my MKV file secure?
Absolutely. Files are processed on isolated servers in Germany, encrypted in transit via TLS, never analysed or shared, and permanently deleted within 24 hours.
Can I batch compress multiple MKV files?
Yes! You can compress up to 5 files per hour on the starter tier. Pro users get 100 files, Business API users get 200. All files are processed in parallel.