20 MB LOG sample

A LOG file of exactly 20,971,520 bytes. It is a valid Log 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 LOG file.

sample-log-20mb.log

20 MB20,971,520 bytes

Download 20 MB LOG

Created in your browser in a few seconds, then checked against the SHA-256 checksum. No sign-up.

Type: text/plain
SHA-256: 40e4ce45363e81ab7b6f3b22ebd362d3ecb7398d5662c5bc3a07a011e1eaef88
Delivery: Created in your browser from static generator assets (how it works).

What is in this file

122,874 web-server access log lines in Combined Log Format with increasing timestamps. One final request line carries a lengthened query string so the file reaches the exact size.

Lines	122,875
Format	Combined Log Format (Apache and nginx access logs)
IP addresses	Documentation ranges from RFC 5737
Encoding	UTF-8 (ASCII characters only)
Line endings	LF

How the file begins

The opening lines of sample-log-20mb.log, exactly as they appear in the file.

00000000  31 39 38 2e 35 31 2e 31  30 30 2e 33 20 2d 20 2d |198.51.100.3 - -|
00000010  20 5b 30 31 2f 4a 61 6e  2f 32 30 32 36 3a 30 30 | [01/Jan/2026:00|
00000020  3a 30 30 3a 30 30 20 2b  30 30 30 30 5d 20 22 47 |:00:00 +0000] "G|
00000030  45 54 20 2f 61 73 73 65  74 73 2f 61 70 70 2e 6a |ET /assets/app.j|

Preview

Creates the file in your browser and shows its first 64 KB.

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.

All 20 MB sample files

Use this file for

Measuring download speed from your own server or CDN
Benchmarking ingestion pipelines
Testing log parsers and grok patterns

Testing notes for LOG

Timestamps carry a zone offset. Parsers that drop it shift every event.
Request paths and user agents come from clients and may contain quotes or escape sequences; a pattern that assumes clean input will misparse real traffic.

LOG format reference

Technical details

File name	sample-log-20mb.log
Format	LOG (Log file)
Extension	.log
MIME type	text/plain
Size	20,971,520 bytes (20 MB)
Kind	Text
SHA-256	40e4ce45363e81ab7b6f3b22ebd362d3ecb7398d5662c5bc3a07a011e1eaef88
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	Available on this page
Source	Generated in your browser by this site's generator; not copied from elsewhere
Licence	Free to use, modify and redistribute (terms)
Category	Testing

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-log-20mb.log     # Linux
shasum -a 256 sample-log-20mb.log # macOS

On Windows, run Get-FileHash sample-log-20mb.log -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 LOG file?: 122,874 web-server access log lines in Combined Log Format with increasing timestamps. One final request line carries a lengthened query string so the file reaches the exact size.
Are the IP addresses real?: No. They come from the address ranges that RFC 5737 reserves for documentation, so they belong to no one.

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