The PDF corner

Password-protect a PDF, or open one

The direction is deduced from the file: a document in the clear gets locked, a protected document gets opened. The method is shown before the act, revision included, and the file you get is REOPENED to check that it really opens.

.pdf80 MB

Drop your PDF hereIn the clear to protect it, or already protected to open it. Nothing will be sent, and the password never leaves this tab.Choose a file

This file is beyond what this tool does

This tool needs JavaScript to work, and that is precisely because it works ON YOUR DEVICE: without JavaScript, your file would have to be sent to a server. The instructions and the limits of the tool, however, can be read without JavaScript, just below.

How this is built

Your file never leaves your device

This tool works entirely inside your browser. Not one byte of your file is sent anywhere, and nothing is kept once the tab is closed.

Checkable in ten seconds, without taking our word for it:

Open your browser's inspector: the F12 key (or Ctrl+Shift+I, or Cmd+Option+I on a Mac).
Go to the “Network” tab, then clear the list.
Process a file on this page. The list stays empty: no request goes out.
To go further: cut your connection and do it again. The tool still works.

This absence of requests is also checked BY MACHINE before every release: a lock drives a real browser, processes a real file, and refuses to publish if a single byte goes out.

The proof page, step by step and in pictures

Going further

InstructionsHow it works

PDFs only. To put any other kind of file under a password, the “Encrypt and decrypt a file” tool in the security corner uses stronger encryption with a slow key derivation: that is the right choice whenever the PDF format is not mandatory.

VerifyThe proof, step by step

The network inspector check, explained one gesture at a time, with screenshots.

The cornerThe PDF corner

The other tools in this corner of the workshop.

UnderstandHow this is built

The formats actually handled, browser by browser, and what we ruled out.