Protect PDF

About this tool

This free Protect PDF tool adds a password to a PDF. Once it is protected, anyone who opens the file — in Acrobat, Chrome, Edge, Preview or on a phone — has to type that password first.

The file is encrypted with AES-128, the same standard encryption Acrobat uses, and it all happens in your browser. Your document and your password are never uploaded, so a confidential contract, payslip or report never leaves your computer.

Restrict printing, copying and editing

Beyond the open password you can also decide what people are allowed to do with the document. Untick any action to block it:

• Printing — stop the PDF being printed
• Copying text and images — stop content being selected and pasted elsewhere
• Editing the content — stop changes to the text and graphics
• Adding comments — stop annotations and sticky notes
• Filling in forms — stop form fields being completed
• Adding, deleting or rotating pages — stop the document being reorganised

You can set a separate permissions password so that only you can lift those restrictions later, while everyone else opens the file with the normal password.

Features

• Add an open password to any PDF — AES-128 encryption
• Optionally restrict printing, copying, editing, comments, forms and page changes
• Optional separate permissions (owner) password
• Password strength meter and a confirm field, so you don't lock yourself out of a typo
• Works fully in your browser — nothing uploaded, nothing stored
• No sign-up, no watermark, completely free

Common uses

• Send an invoice, contract or offer letter by email without it being readable by anyone who intercepts it
• Protect payslips, HR records or medical documents before sharing them
• Lock a quotation or price list so the client can read it but not edit or copy the numbers
• Add a password to board papers or financial reports before they are circulated

Good to know

• Keep your password somewhere safe. Nobody — including this site — can recover or reset it. If the password is lost, the document is lost.
• If your PDF already has a password, remove it first with the Unlock PDF tool and then protect it again.
• Permission restrictions are honoured by mainstream readers, but they rely on the reader behaving. The open password is the part that really encrypts the file.

How to use it

• Upload the PDF — click the upload area or drag your file in
• Choose a password — type it twice so a typo can't lock you out
• Restrict actions (optional) — open the extra options and untick printing, copying or editing
• Protect & download — click Protect PDF, then Download to save the encrypted copy