Free MKV sample files
An open container that holds almost any codec, with many audio and subtitle tracks in one file. Download valid MKV test files in 4 exact sizes, from 100 KB to 5 MB, each with a checksum.
- Extension
- .mkv
- MIME type
- video/x-matroska
- Kind
- Binary
- Category
- Video
MKV files by size
Every file below is a valid Matroska video file of exactly the stated size. Open a file's page for its checksum and contents. MKV files cannot be displayed by a browser, so their pages show the file's details instead of a preview.
| File | Size | Contents | Download |
|---|---|---|---|
| 100 KB MKV samplesample-mkv-100kb.mkv | 100 KB102,400 bytes | 640 × 360 px | Download MKV |
| 500 KB MKV samplesample-mkv-500kb.mkv | 500 KB512,000 bytes | 640 × 360 px | Download MKV |
| 1 MB MKV samplesample-mkv-1mb.mkv | 1 MB1,048,576 bytes | 640 × 360 px | Download MKV |
| 5 MB MKV samplesample-mkv-5mb.mkv | 5 MB5,242,880 bytes | 640 × 360 px | Download MKV |
What is an MKV file?
Matroska is a container built on EBML, a binary relative of XML in which every element has an ID, a length and a payload. A file can carry any number of video, audio and subtitle tracks along with chapters, tags and attachments, and it places almost no restriction on the codecs used.
Picture data is grouped into clusters, and an index called Cues records where each key frame is. The format was published as an internet standard, RFC 9559, in 2024, after two decades as a de facto one.
How to recognise an MKV file
Software recognises an MKV file by its file signature: fixed bytes at the start of the file, also called magic bytes or a magic number.
| Extension | .mkv |
|---|---|
| MIME type | video/x-matroska |
| Also seen as | video/matroska |
| Standard | RFC 9559 (Matroska) and RFC 8794 (EBML) |
| Structure | EBML header, then a Segment of Info, Tracks, Cues and Clusters |
| Codecs | Almost any: H.264, HEVC, AV1, VP9, AAC, FLAC, Opus and more |
| Related extensions | .mka audio, .mks subtitles, .webm |
What to test for
These are the behaviours that most often go wrong when software handles MKV files.
- MKV and WebM share a signature. Detection has to read the document type inside the EBML header: "matroska" or "webm".
- Safari and Firefox do not play MKV, and Chrome does so only for some codecs. Remux to MP4 or WebM before showing video in a page.
- A file with no Cues element still plays but cannot seek quickly. Recordings that were interrupted, and live captures, are often like this.
Strengths of MKV
- Holds almost any codec, with unlimited audio and subtitle tracks.
- An open standard, and resilient: a damaged file can usually be played up to the damage.
Limitations of MKV
- Not playable in Safari or Firefox.
- Flexibility cuts both ways: a player may support the container and still not the codecs inside.
Typical uses of MKV test files
- Testing video upload beyond MP4
- Checking transcoding and remuxing pipelines
- Verifying type detection between MKV and WebM
- Testing media servers and players with a seekable file
Software that opens MKV
- VLC and mpv
- MKVToolNix and FFmpeg
- Windows 10 and 11, and Android, natively
- Plex, Kodi and Jellyfin
- OBS Studio, which can record to MKV
Specifications
Related
MKV sample files: questions
- Which codec do the MKV samples use?
- H.264 video at 640 × 360 and 30 frames per second, with no audio track. The index of key frames is at the front of the file.
- Which media type should a server send for MKV?
- Most software uses video/x-matroska. RFC 9559 registered video/matroska in 2024, and an allow-list should accept both.
- What is the MIME type of an MKV file?
- The MIME type is video/x-matroska. You will also meet video/matroska in practice. The file extension is .mkv.
- Is a sample MKV file the same as a dummy or example MKV file?
- Yes. Sample, test, dummy and example MKV files are different names for the same thing: an MKV file with known contents that stands in for a real one. Any file on this page will do wherever a tutorial or a test plan asks for a dummy MKV file.