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Protect PDF

Add password protection to any PDF in your browser. Set an open password, restrict printing and copying, and control permissions — nothing is ever uploaded.

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Password Protect Your PDF

Set an open password that recipients must enter to view the file, or restrict what they can do with it using a permissions password.

Drop your PDF here
or click to browse — one PDF at a time
PDF
Loaded File
PDF
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Section 1 — Owner Password
This password opens the file and bypasses all restrictions set in Section 3. Keep it for yourself — do not share it with recipients.
Section 2 — Open Password
Give this password to recipients you want to be able to view the file. They will need it just to open the PDF — but will still be subject to any restrictions set in Section 3.
Section 3 — Restrictions
These restrictions apply to anyone who opens the file with the open password. They can only be bypassed by someone with the owner password from Section 1.
Output Filename
.pdf
PDF Protected & Downloaded!

Your password-protected PDF has been saved to your device.

How to Password Protect a PDF

PDFToolShack’s Protect PDF tool runs entirely in your browser using pdf-lib.js. Your file is encrypted locally using AES-128 encryption and the protected PDF downloads directly to your device — no server contact, no stored passwords, no data transmitted.

There are two types of PDF passwords. The open password (user password) must be entered before the PDF can be viewed at all. The permissions password (owner password) doesn’t prevent opening, but controls what readers can do — print, copy, edit, annotate. You can set one, both, or use permissions restrictions without any open password.

Important: We never see or store your password. If you forget it, the PDF cannot be recovered. Always store your password in a safe place such as a password manager.

Frequently Asked Questions

Is my PDF or password sent to your server?
No — never. Encryption happens entirely in your browser using JavaScript. Your file and your password never leave your device. Nothing is transmitted to any server at any point.
What’s the difference between the open password and the permissions password?
The open password must be entered before the PDF can be opened at all. The permissions password (owner password) doesn’t block opening — it restricts what readers can do: print, copy, edit, or annotate. You can use one, both, or just permissions restrictions without an open password.
What encryption does this use?
This tool uses AES-128 encryption via pdf-lib.js, which is the standard for PDF password protection and is compatible with Adobe Acrobat and all major PDF viewers. For highly sensitive documents requiring AES-256, a dedicated desktop application is recommended.
What if I forget the password?
We have no way to recover it — we never see or store your password. If you forget it, the PDF is inaccessible. Always store your password in a password manager before protecting important documents.
Will all PDF readers respect the permissions restrictions?
Major PDF viewers (Adobe Acrobat, Preview on Mac, Edge, Chrome) respect permissions restrictions. However, some third-party tools and PDF editors may ignore them. For critical documents, an open password provides stronger protection since it prevents access entirely without the correct password.
Can I protect a PDF that’s already password protected?
You’ll need to unlock it first using our Unlock PDF tool, then re-protect it with the new password here.