20 MB GZ sample
A GZ file of exactly 20,971,520 bytes. It is a valid Gzip compressed file file, generated by this site. Compare its checksum and test it with the parser used by your application. Use it wherever you need a 20 MB sample, test or dummy GZ file.
Download
sample-gz-20mb.gz
20 MB20,971,520 bytes
Download 20 MB GZCreated in your browser in a few seconds, then checked against the SHA-256 checksum. No sign-up.
- Type
- application/gzip
- SHA-256
5b593be40ec0cac72c58ecfcc2cb8b2147c033f362b47bfc7a1e95517411ef5c- Delivery
- Created in your browser from static generator assets (how it works).
What is in this file
One gzip member that expands to sample.log, 1,042,206 access-log lines (177,941,529 bytes). 4,090 bytes of text in the optional gzip header comment field bring the file to the exact size.
| Compressed member | sample.log |
|---|---|
| Uncompressed size | 177,941,529 bytes |
| Compression method | Deflate |
| Members | 1 |
| Original file name stored | Yes |
First bytes of the file
The first 64 bytes of sample-gz-20mb.gz as a hex dump: offset, bytes, then the same bytes as text. The GZ signature is 1F 8B 08.
00000000 1f 8b 08 18 00 b9 55 69 00 03 73 61 6d 70 6c 65 |......Ui..sample|
00000010 2e 6c 6f 67 00 53 61 6d 70 6c 65 54 65 73 74 46 |.log.SampleTestF|
00000020 69 6c 65 73 20 73 61 6d 70 6c 65 20 61 72 63 68 |iles sample arch|
00000030 69 76 65 2e 20 41 6c 69 67 6e 6d 65 6e 74 20 70 |ive. Alignment p|Preview
GZ files cannot be shown in a browser. Download the file and open it in an application that reads GZ, such as gzip and gunzip.
Where 20 MB matters
A 20,971,520-byte file: right at the default attachment limit of Outlook, and just under the 25 MB ceilings of Gmail and GitHub web uploads. These are the default limits a file of this size is useful for testing:
| System | Limit | Note |
|---|---|---|
| Microsoft Outlook | 20 MB of attachments by default for internet mail accounts | This file is right at the limit; add a second attachment and it is exceeded. |
| Gmail | 25 MB per message | Under the limit, although email encoding adds about a third in transit. |
| GitHub web uploads | 25 MiB per file added through the browser | Accepted. Pushing with Git allows larger files. |
| Cloudflare Pages assets | 25 MiB per file | The largest round size that can be served as a static asset. |
| Amazon API Gateway | 10 MB payload | Rejected; the upload has to go directly to object storage. |
| ASP.NET Core (Kestrel) | About 28.6 MB request body by default | Accepted with room for the multipart overhead. |
Use this file for
- Measuring download speed from your own server or CDN
- Testing streaming decompression
- Testing decompression of uploads and log archives
Testing notes for GZ
- A small .gz can decompress to gigabytes. Stream and cap the output rather than inflating it into memory.
- If a server sends a .gz file with Content-Encoding: gzip, the client transparently decompresses it and saves a file whose content does not match its name.
Technical details
| File name | sample-gz-20mb.gz |
|---|---|
| Format | GZ (Gzip compressed file) |
| Extension | .gz |
| MIME type | application/gzip |
| Size | 20,971,520 bytes (20 MB) |
| Kind | Binary |
| Signature | 1F 8B 08 |
| SHA-256 | 5b593be40ec0cac72c58ecfcc2cb8b2147c033f362b47bfc7a1e95517411ef5c |
| Created | 2026-10-23 |
| Validation | See the listed size and SHA-256. Small downloads are checked in the browser; verify streamed downloads manually. A hash match does not prove parser compatibility. |
| Preview | Not available for this file; details only |
| Source | Generated in your browser by this site's generator; not copied from elsewhere |
| Licence | Free to use, modify and redistribute (terms) |
| Category | Archives |
Check the stated structure and checksum against your application requirements. As with any download, scan the file with your own security tools before opening it. How files are made and checked
Verify your copy
This file is created in your browser, so it has no direct URL for curl or wget. The generator is designed to produce reproducible bytes. After saving, compare the checksum with the SHA-256 value above.
sha256sum sample-gz-20mb.gz # Linux
shasum -a 256 sample-gz-20mb.gz # macOSOn Windows, run Get-FileHash sample-gz-20mb.gz -Algorithm SHA256 in PowerShell. For scripts and pipelines, save the file once and keep your own copy.
Related files
Questions about this file
- Is this file exactly 20 MB?
- Yes. It is 20,971,520 bytes, which is 20 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
- What is inside the 20 MB GZ file?
- One gzip member that expands to sample.log, 1,042,206 access-log lines (177,941,529 bytes). 4,090 bytes of text in the optional gzip header comment field bring the file to the exact size.
- What do the sample .gz files decompress to?
- A text file named sample.log containing web-server access log lines. The uncompressed size is shown on each download page.