PDF security tools

Controlling who can open a document and what it gives away. Add password to PDF encrypts the file so a viewer asks for the password before it renders anything; Remove PDF password does the reverse when you know the password and no longer want to type it every time. Neither is a way around a password you were never given.

Redact PDF removes the content under the areas you mark, which is the tool to use when a name or an account number has to genuinely be gone — a black rectangle drawn as an annotation can be dragged aside in another viewer, and the text is still there underneath. Edit PDF metadata rewrites the title, author, subject and keywords that travel with the file and that most people forget exist at all; they are a common accidental leak when a document is repurposed from an old template. Sign PDF places a drawn or uploaded signature image on a page, for the everyday case of returning a signed form to someone.

A security tool that asks you to upload the document first is working against its own purpose. Everything in this category runs inside the browser tab, so the unencrypted original, the password you type and the text you redact are all handled on your own device and nowhere else.