Privacy Policy

Last updated: August 24, 2026

Summary

DiffLab is a browser-based comparison tool. Your pasted text, list data, and JSON are processed entirely in your browser. We do not run a backend application server, and your input content is never transmitted to or stored on any server controlled by us.

What stays on your device

• Pasted text: All text you type or paste into the comparison boxes is processed locally in the browser using JavaScript. It is never sent over the network.
• JSON data: JSON pasted into the JSON Compare tool is parsed and diffed entirely in your browser. No JSON content is sent to any server.
• List data: List items you paste into the List Compare tool are processed locally. No list content is transmitted.

File upload and CDN libraries

The Text Compare tool supports drag-and-drop file uploads for .txt, .docx, .xlsx, and .pdf files. When you drop a file, the browser parses it locally using third-party libraries loaded from a CDN (cdnjs.cloudflare.com):

• Mammoth.js (for .docx files)
• SheetJS (xlsx) (for .xlsx/.xls files)
• pdf.js (for .pdf files)

These libraries are downloaded from the CDN so your browser can parse the file format. The library scripts are loaded from the CDN, but your actual file content is never uploaded to the CDN or any other server. The file is read by the browser in memory (via FileReader API), parsed locally, and the extracted text is placed into the textarea. The original file bytes are never sent to any server.

Analytics

This site uses Cloudflare Web Analytics, a privacy-first analytics service. Cloudflare Web Analytics collects aggregated, anonymized usage metrics (such as page views and country-level location) without using cookies or tracking individual users. It does not set any cookies in your browser. You can read more about Cloudflare Web Analytics and its privacy properties at cloudflare.com/web-analytics.

Cookies and local storage

DiffLab does not set any cookies. DiffLab does not use browser local storage or session storage to store your data. No user accounts, preferences, or input history are stored. When you close the page, all input is gone.

Server logs

The site is hosted on Cloudflare Pages. Cloudflare may automatically log standard HTTP request data (such as IP address, timestamp, and requested URL) as part of its normal infrastructure operation. These logs are managed by Cloudflare under its own privacy policy and are not directly accessible to us. We do not run our own backend server that collects or stores your data.

What we do not do

• We do not collect or store your text, lists, JSON, or file content.
• We do not require accounts, sign-ups, or logins.
• We do not use tracking cookies or advertising trackers.
• We do not sell or share data with third parties.
• We do not embed social media widgets or third-party comment systems.

Third-party resources

Your browser loads the following third-party resources when you visit DiffLab:

• cdnjs.cloudflare.com: Serves the file-parsing libraries (mammoth, xlsx, pdf.js) when needed. This CDN may log requests.
• static.cloudflareinsights.com: Serves the Cloudflare Web Analytics beacon script.

No third-party resource receives your input content.

Children's privacy

DiffLab is a general-purpose utility tool and is not directed at children under 13. We do not knowingly collect personal information from children.

Changes to this policy

If we update this privacy policy, we will change the "Last updated" date above. We recommend reviewing this page periodically.

Contact

If you have questions about this privacy policy, please open an issue on our GitHub repository.