File safety

Last updated: 10 October 2026

Downloading files from a website you have just found deserves some caution. This page explains exactly where our files come from, what is in them and how you can verify them yourself.

Where the files come from

Every sample file on SampleTestFiles is produced by our own generator. Nothing is uploaded by users, collected from the internet or converted from third-party documents. The generator writes each format directly from its published specification, using text and images that it creates itself.

What the files do not contain

• No executable code. There are no programs, installers, scripts or libraries. We do not publish .exe, .dll, .msi, .apk, .sh or similar files.
• No macros. Office documents are plain .docx, .xlsx and .pptx files, which cannot hold macros.
• No active content. PDFs contain no JavaScript, forms or attachments. SVG and HTML samples contain no scripts and load nothing from other sites.
• No tracking. Files contain no remote images, web beacons or links that report back when opened.
• No personal data. People, companies and addresses are invented. Email addresses use example.com, example.org and example.net, which are reserved for documentation. IP addresses in log samples come from ranges reserved for the same purpose.
• No copyrighted media. Images are a generated test card. Audio is a synthesised phrase. Video is a synthetic test pattern.

What the files do contain

Each download page lists the contents of that file: page counts, pixel dimensions, row counts, duration and so on, along with a short account of how the file was built.

To make a file land on an exact byte count, the generator sometimes adds a small amount of padding. It always uses a mechanism that the format provides for the purpose, for example a comment in a PDF or a JPEG, or the padding area of an ID3 tag. Where padding is used, the download page says how many bytes and where they are.

The binary (.bin) samples are pseudo-random bytes with no structure. They are inert data and cannot be run.

How files are checked

Before publication, every file is:

1. Verified to be exactly the stated size.
2. Checked for the correct signature bytes of its format.
3. Opened with an independent parser or decoder for that format. Images are fully decoded, documents are opened, archives are extracted, audio and video are decoded from start to finish, and data files are parsed.

A file that fails any check is not published.

Verify a download yourself

Each download page shows the file's size in bytes and its SHA-256 checksum. After downloading, compute the checksum and compare.

On Linux:

sha256sum sample-pdf-1mb.pdf

On macOS:

shasum -a 256 sample-pdf-1mb.pdf

On Windows, in PowerShell:

Get-FileHash .\sample-pdf-1mb.pdf -Algorithm SHA256

If the result matches the value on the page, the file you have is identical to the one we published. If it does not match, the download was incomplete or was altered on the way; delete it and try again.

A machine-readable list of every file with its size and checksum is available at /files.json.

Sensible precautions

• Use sample files in a test or development environment, as you would any test data.
• Scan downloads with your own security software as a matter of routine. If a tool flags one of our files, please let us know.
• Download only from this site. We cannot vouch for copies hosted elsewhere.

Advertisements

The site carries advertising, which is labelled as such and kept visually separate from download buttons. Our download buttons are green and name the file and its size. Nothing on this site will ask you to install software, a browser extension or a "download manager" in order to get a file.

What we can and cannot promise

Each file is validated for its expected format and integrity before it is published. That is a statement about how the files are made, not a guarantee about your environment. No website can certify a download as risk-free for every system, so scan downloaded files with your own security tools before opening them, as you would with any file from the internet.

Reporting a security problem

If you find a security problem with the site or with a file, email contact@sjwebtechwork.com with the address of the page or file and a description of what you found. Please give us a reasonable time to fix it before making it public. The same contact is published in machine-readable form at /.well-known/security.txt.

Report a problem

If a file appears damaged, is flagged by security software or does not match its checksum, email contact@sjwebtechwork.com with the file name and what you observed. We will investigate and correct it.