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  3. PDF Password Protector
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PDF Password Protector

Encrypt and password-protect your PDF documents. Set user and owner passwords, control printing, copying, and editing permissions with 128-bit AES encryption.

Set a password on your PDF so it cannot be opened without the correct credentials. The tool encrypts your document entirely in your browser, so the file and password never leave your device. You can set a user password (required to open the file) and, optionally, a separate owner password. A password strength meter and a one-click strong-password generator help you pick something hard to guess.

PDFs never leave your deviceMore pdf toolsJump to full guide

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PDF Password Protector: a worked example

A payslip PDF must be encrypted with a password before emailing it.

Input

payslip.pdf + open password · 128-bit AES
PDF Password Protector produces

Output

payslip.pdf, encrypted; opening it now requires the password

The PDF is encrypted with 128-bit AES so its contents are unreadable without the password, and you can also set a separate permissions password to restrict printing or copying. Encryption happens in the browser, so the sensitive document is never uploaded.

About the PDF Password Protector

Set a password on your PDF so it cannot be opened without the correct credentials. The tool encrypts your document entirely in your browser, so the file and password never leave your device. You can set a user password (required to open the file) and, optionally, a separate owner password. A password strength meter and a one-click strong-password generator help you pick something hard to guess.

Working with your PDF

  1. 1Upload the PDF you want to protect.
  2. 2Enter a password to open the document (and optionally a separate owner password).
  3. 3Optionally use the generator to create a strong password and copy it.
  4. 4Download the encrypted PDF.
  5. 5Share the password with authorized recipients through a separate channel.

Key features

  • User password required to open the document
  • Optional separate owner password
  • RC4 128-bit PDF encryption applied entirely in your browser
  • Password strength meter and strong-password generator
  • Compatible with standard PDF readers

Common scenarios

  • Confidential business documents

    Protect financial reports, contracts, or strategic plans before sending them over email.

  • Client deliverables

    Require a password before proposals or design files delivered to clients can be opened.

  • Personal records

    Add a password to tax returns, medical records, or other sensitive personal documents stored in the cloud.

  • Restricting access

    Require a password before anyone can open published or distributed materials.

Tips & best practices

  • Always share passwords through a different channel than the document itself, for example, send the PDF by email and the password by text message.
  • Use the built-in generator to create a strong password, then store it in a password manager so you do not lose access.

How it works

Encryption is performed client-side using the pdf-encrypt-lite library, which implements RC4 128-bit PDF encryption (the PDF Standard Security Handler). The PDF is first loaded and saved with pdf-lib, then encrypted with your user password and an owner password (the user password is reused as the owner password if you do not set a separate one). The resulting file prompts for the password in standard PDF readers.

A note on permissions: the interface lets you toggle permissions such as printing, copying, and editing, but the current encryption step applies the open password protection rather than enforcing those individual permission flags in the output, so treat them as intended settings rather than guaranteed restrictions. RC4 128-bit is older than modern AES-256 encryption; it keeps casual readers out and is widely compatible, but for highly sensitive material you may want stronger, dedicated encryption.

Frequently asked questions

What is the difference between the user password and the owner password?

The user password is required to open the document. You can also set a separate owner password; if you leave it blank, the user password is used for both. In this tool both are about controlling access via encryption rather than enforcing fine-grained print/edit permissions.

Can I remove a password from my PDF?

This tool adds password protection rather than removing it. To take a password off, you would need a separate unlock tool and knowledge of the current password.

How strong is the encryption?

It uses RC4 128-bit PDF encryption, which is widely compatible and keeps casual readers out. It is older than AES-256, so for highly sensitive documents consider stronger, dedicated encryption or secure file transfer.

Private by design

PDF parsing and editing happen in your browser. Documents, and everything inside them, are never uploaded or stored remotely.