Guides / PDF privacy

Is It Safe to Merge PDF Files Online?

Many online PDF tools send your files to a server to combine them. That can be fine for a public brochure, but it is worth checking before you upload a contract, a payslip or an ID document.

How most online merge tools work

Most websites that merge PDFs upload the files to their servers, combine them there, and let you download the result. Some delete the files after a short time, and others keep them longer. The details are usually in their privacy policy.

What to check before you upload

• Does the site say whether files are uploaded, and where they are stored?
• How long are files kept, and can you delete them yourself?
• Is the site secured with HTTPS, and does it name the company behind it?

How Toolkit Lab works

The Merge PDF tool loads a small library into your browser and combines the pages on your device. Your files are not sent to our servers. You can check this yourself: open your browser's developer tools, switch to the network tab, merge a file, and see that no upload request is made.

Sensitive documents

For highly confidential documents, a desktop PDF app or the built-in tools on your computer keep the files entirely local. Whatever tool you use, check that you can access the merged file and delete the originals when you are finished.