How does PDFCommunity work?

The technology

PDFCommunity is a website like any other: your browser downloads its pages, styles and scripts from www.pdfcommunity.org. The difference is what happens next. Everything a tool does runs as JavaScript in your browser, on your own device, with a few well-known open-source libraries:

• pdf.js (from Mozilla) reads PDFs: page previews, turning pages into images, and reading text and layout for a conversion to Word or PowerPoint. It does its heavy work in a Web Worker, a background thread of your browser, so the page stays usable.
• pdf-lib creates and edits PDFs: merging, splitting, rotating, page numbers, watermarks and more.
• JSZip, docx and PptxGenJS put together ZIP files, Word documents and PowerPoint presentations.

These libraries are served from this site itself, not from an outside server. Their exact versions and licenses are listed on Open-source licenses.

What does go over the internet

Opening a page uses the internet, just like any other website:

• The site itself: pages, styles, scripts, fonts and the PDF libraries, all from www.pdfcommunity.org.
• A visitor counter: Cloudflare Web Analytics counts visits without cookies and without a visitor profile. It reports that a page was visited, not what you do with a file.
• Google Analytics, only if you accept it in the cookie banner. If you decline or make no choice, it is not loaded at all.

You can read the details, including how long data is kept, in our privacy policy.

What doesn't go over the internet

Your files. Not their content, not their names, and nothing a tool reads from them or makes out of them. They are not sent to us, to Cloudflare, to Google or to anyone else. The site's server only hands out its own pages and scripts; it has no function for receiving your files. When you pass a file or a result on to another tool, it waits for a moment in your browser's own storage, on your device, and is deleted as soon as the next tool has picked it up.

Check it yourself

You don't have to take our word for it. Every browser can show what a page sends. On Verify it yourself we explain in three steps how to watch the network traffic while you use a tool: an upload would be as big as your file, and you won't find one. While a tool is working, it also shows how much was processed on your device and that 0 bytes of your files were uploaded.

Check our security headers yourself. Our server also sends security headers, such as a Content Security Policy that sets which scripts the page may load and which addresses it may connect to. Two independent scanners test them: Mozilla HTTP Observatory and securityheaders.com. See the current score there.

Working offline

Once you have opened the site online, a service worker keeps a copy of its pages, scripts, styles, fonts and PDF libraries in your browser. That is why most tools keep working without internet, for example on a train. A watermark with special characters or a non-Latin script, and some PDFs with Asian text, need an extra file that is only downloaded the first time it's needed. The offline copy doesn't contain your files.

Limits

Because your own device does the work, its memory sets the limit, not a server. On a regular laptop or phone, documents with hundreds of pages usually work fine. Very large files can be too much for an older phone or tablet: the tools warn you when a file is large, and if memory still runs out, the browser may stop the page. Your original file is never changed, because a tool only reads it and makes a new file. Tip: split a very large PDF first, or use a computer.

For press, schools and directories

You are welcome to quote this page and link to it. In one sentence: PDFCommunity is a free set of PDF tools in eight languages that does all its work in the visitor's own browser, so files aren't uploaded. Questions? Email support@pdfcommunity.org.

Try the tools