The short version

The full terms are below. They cover the edge cases and legal bases that the summary glosses over. If you use the site regularly, it's worth reading.

1   What this site is and what you're agreeing to

21K Tools (https://21k.tools) is an educational platform that explains how common digital tools and formats work, and provides those tools free of charge on the same pages. Content includes written guides, comparison tables, FAQs, and working tools for PDF manipulation, image processing, QR code generation, URL shortening, file conversion, and various calculators.

By accessing or using the site, you agree to be bound by these Terms and by the Privacy Policy. These Terms apply to everyone who uses the site — visitors, tool users, and people reading the guides.

If you're using the site on behalf of a company or organisation, you're representing that you have the authority to bind that organisation to these Terms.

2   How to use this site — and how not to

The tools and guides on 21K Tools are provided for legitimate personal, educational, and professional use. You agree not to use the site in the following ways:

• Uploading, processing, or distributing content that is illegal, harmful, abusive, defamatory, or infringes on someone else's rights
• Using the tools to process content that violates the intellectual property rights of others
• Attempting to interfere with, disrupt, or overload the site's infrastructure or servers
• Using automated bots or scraping tools to access or use the services excessively
• Attempting to gain unauthorised access to any part of the site or its systems
• Uploading files that contain malware, viruses, or other malicious code
• Misrepresenting who you are or impersonating anyone else

A note on file uploads

When you upload a file to any tool on this site, you're representing that you own it or have the right to use and process it, and that the file doesn't contain material that violates anyone's rights or any applicable law. For the browser-based tools — which is most of them — your file never leaves your device, so the practical risk is low. For the URL shortener and QR code file upload feature, server storage is involved and the same representation applies.

3   Intellectual property — what belongs to whom

Everything on 21K Tools that was created for this site — the written guides, the tool interfaces, the design, the code, the educational content — is owned by 21K Tools and protected by copyright. You can read it, use the tools, share links to it, and quote short sections with attribution. You can't reproduce the guides in full, scrape the content for your own site, or present the work as your own.

Your files are yours. When you upload something to a tool, you keep full ownership of it. By using the tools, you grant us a limited, temporary licence to process your file for the purpose of delivering the result you requested — nothing more. For browser-based tools this is academic since the file never leaves your device anyway. For the URL shortener and QR file upload, the processing and storage is what makes the service work.

The educational content on this site — the guides explaining how QR codes encode data, how PDF compression works, how redirect chains function — is original writing and subject to standard copyright. You can use the knowledge freely. Copying the writing is a different matter.

4   What we provide and what we don't guarantee

The tools and guides on 21K Tools are provided free of charge on an "as-is" and "as-available" basis. That means:

• We don't guarantee the site will be available at all times without interruption
• We don't guarantee any particular tool will produce error-free results in every case
• We don't guarantee the educational content is exhaustive or covers every possible scenario
• We don't guarantee that third-party services we rely on (like Cloudinary for QR file uploads) will always be available

In practice, the tools work reliably for standard use cases. But edge cases exist — heavily encrypted PDFs, obscure file structures, unusually large files — where results may not be what you expect. The FAQ on each tool page covers the most common issues.

The site is not professional advice

The guides explain how digital tools and formats work. They're not legal advice, financial advice, medical advice, or any other form of professional guidance. If the content touches on something where professional advice matters, get it from an actual professional.

Limitation of liability

To the extent permitted by applicable law, 21K Tools is not liable for indirect, incidental, or consequential damages arising from your use of the site — including data loss, processing errors, or the results produced by any tool. For the free tools, the maximum liability is the amount you paid to use them, which is zero.

This doesn't mean we're indifferent to problems. If a tool produces an incorrect result or causes an issue, we want to know. But the legal liability for using free online tools is something users need to account for, especially for anything that matters professionally.

5   Changes, availability, and termination

We can modify, update, remove, or add tools and content at any time. If a tool is discontinued, it's removed. If a guide is updated with better information, it gets updated. The site is a living thing and will keep changing.

If we make a material change to these Terms — something that meaningfully affects how the site works or what rights you have — we'll post a notice on the site and update the date at the top of this page.

We can restrict access for anyone who is abusing the site, using it for illegal purposes, or causing harm to the site or other users. Continued use after any Terms update means acceptance of the new Terms.

6   Third-party links and services

Some pages link to external sites and resources. 21K Tools is not responsible for the content, privacy practices, or availability of any third-party site. Links to external resources — documentation, official standards, related tools — are provided for convenience and don't constitute endorsement.

The QR code file upload feature uses Cloudinary for file hosting. The URL shortener runs on our own infrastructure. For all other tools, no third-party services are involved in processing your data.

Advertising

21K Tools currently displays no advertising — the site is completely ad-free. We may add Google AdSense in the future to help sustain the free tools and content. If that happens, these Terms will be updated to reflect it, and the change will be announced on the site before ads go live.

7   Disputes and governing law

These Terms are governed by the laws of the jurisdiction in which 21K Tools operates. If a dispute arises from the use of this site, the first step is to try to resolve it by emailing us at contact@21k.tools. Most issues can be sorted that way.

If informal resolution doesn't work, disputes may be submitted to mediation or arbitration as agreed by both parties. Any dispute resolution happens on an individual basis — not as part of a class action.

If any provision of these Terms is found unenforceable, the rest of the Terms continue in full force.

8   Contact and questions

If something in these Terms is unclear, you disagree with something, or you have a question that isn't answered here, reach out:

• Email: contact@21k.tools
• Help Center: https://21k.tools/help
• Website: https://21k.tools

We respond to everything. These aren't Terms written to avoid all contact — they're written to make the site's rules clear so there are fewer reasons to need to contact us in the first place.

Last Updated: February 10, 2026