1 MB MKV sample file
An MKV file of exactly 1,048,576 bytes. It is a valid Matroska video file, generated for this site and checked with an independent parser. Use it wherever you need a 1 MB sample, test or dummy MKV file.
Download
sample-mkv-1mb.mkv
1 MB1,048,576 bytes
Download 1 MB MKVDirect download. No sign-up and no waiting.
- Type
- video/x-matroska
- SHA-256
d9fdbb1247228c25c75c57b2eb17072f2830738b4d604224912d781ca0c59b0c- Direct URL
https://www.sampletestfiles.com/downloads/mkv/sample-mkv-1mb.mkv
What is in this file
561 frames (18.7 s) of a synthetic test pattern with a frame counter, looping every six seconds, in one H.264 (AVC) video track. The index of key frames comes before the picture data, so a player can seek without reading the whole file. 1,286 bytes of an EBML Void element bring the file to the exact size.
| Dimensions | 640 × 360 px |
|---|---|
| Duration | 18.7 s |
| Frame rate | 30 fps |
| Video codec | H.264 (AVC), Main profile |
| Audio | No audio track |
| Document type | matroska |
| Clusters | 19, one for each key frame |
| Seek index | Cues element before the first cluster |
First bytes of the file
The first 64 bytes of sample-mkv-1mb.mkv as a hex dump: offset, bytes, then the same bytes as text. The MKV signature is 1A 45 DF A3.
00000000 1a 45 df a3 a3 42 86 81 01 42 f7 81 01 42 f2 81 |.E...B...B...B..|
00000010 04 42 f3 81 08 42 82 88 6d 61 74 72 6f 73 6b 61 |.B...B..matroska|
00000020 42 87 81 04 42 85 81 02 18 53 80 67 01 00 00 00 |B...B....S.g....|
00000030 00 0f ff cc 15 49 a9 66 cc 2a d7 b1 83 0f 42 40 |.....I.f.*....B@|Preview
MKV files cannot be shown in a browser. Download the file and open it in an application that reads MKV, such as VLC and mpv.
Where 1 MB matters
A 1,048,576-byte file: exactly the default upload limit of nginx, Spring Boot and Next.js. These are the default limits a file of this size is useful for testing:
| System | Limit | Note |
|---|---|---|
| nginx | 1 MB by default (client_max_body_size) | A multipart upload of this file exceeds the limit by the size of the form boundaries. |
| Spring Boot multipart | 1 MB per file by default (max-file-size) | A file of exactly 1 MB is at the limit. |
| Next.js API routes and Server Actions | 1 MB by default | Larger bodies need the size limit raised in configuration. |
| Cloud Firestore documents | 1 MiB (1,048,576 bytes) | The same number of bytes as this file. |
| Apache Kafka messages | About 1 MB by default | Brokers reject larger records unless message.max.bytes is raised. |
Use this file for
- Finding the first upload limit in a new stack
- Testing video upload beyond MP4
- Checking transcoding and remuxing pipelines
Testing notes for MKV
- A file with no Cues element still plays but cannot seek quickly. Recordings that were interrupted, and live captures, are often like this.
- MKV and WebM share a signature. Detection has to read the document type inside the EBML header: "matroska" or "webm".
Technical details
| File name | sample-mkv-1mb.mkv |
|---|---|
| Format | MKV (Matroska video) |
| Extension | .mkv |
| MIME type | video/x-matroska |
| Size | 1,048,576 bytes (1 MB) |
| Kind | Binary |
| Signature | 1A 45 DF A3 |
| SHA-256 | d9fdbb1247228c25c75c57b2eb17072f2830738b4d604224912d781ca0c59b0c |
| Created | 2026-10-10 |
| Validation | Exact size, signature bytes and structure checked when the file was generated |
| Preview | Not available for this file; details only |
| Source | Generated for this site; not copied from elsewhere |
| Licence | Free to use, modify and redistribute (terms) |
| Category | Video |
Validated for expected format and integrity. As with any download, scan the file with your own security tools before opening it. How files are made and checked
Download from the command line and verify
Fetch the file with curl, then compare its checksum with the SHA-256 value above.
curl -o sample-mkv-1mb.mkv 'https://www.sampletestfiles.com/downloads/mkv/sample-mkv-1mb.mkv'
sha256sum sample-mkv-1mb.mkv # Linux
shasum -a 256 sample-mkv-1mb.mkv # macOSOn Windows, run Get-FileHash sample-mkv-1mb.mkv -Algorithm SHA256 in PowerShell. A matching value proves that the download is complete and unaltered.
Related files
Questions about this file
- Is this file exactly 1 MB?
- Yes. It is 1,048,576 bytes, which is 1 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
- What is inside the 1 MB MKV file?
- 561 frames (18.7 s) of a synthetic test pattern with a frame counter, looping every six seconds, in one H.264 (AVC) video track. The index of key frames comes before the picture data, so a player can seek without reading the whole file. 1,286 bytes of an EBML Void element bring the file to the exact size.
- 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.