Protect & Unlock PDF — password, encrypt, free and private

Add a password to protect a PDF with AES-256 or RC4 encryption, set print and copy permissions, or unlock a password-protected PDF you can open. Everything runs in your browser, so the file and its password are never sent to our servers.

How to protect or unlock a PDF

  1. Drop your PDF into the box above, or click to choose a file.
  2. Choose Protect to add a password, or Unlock to remove one you know.
  3. To protect: set a password, pick permissions and AES-256 or Compatible encryption. To unlock: type the password.
  4. Click Encrypt & Download (or Unlock PDF) — it all runs locally in your browser.
  5. Download the protected or unlocked PDF. The original is never uploaded to our servers.

What it does

  • Real AES-256 or RC4-128 password encryption, set entirely on your device
  • Permission presets to allow or block printing, copying, editing, and annotations
  • Unlock any password-protected PDF you can already open, with no software to install
  • No watermark, no sign-up, no file or password ever uploaded

Common uses

  • Password-protecting a contract, tax return, or medical record before emailing it
  • Sharing a report read-only by blocking copy and edit while still allowing print
  • Removing the password from your own PDF so you can merge or edit it later

Is it private?

Yes. Unlike most "protect PDF online" tools, PaperFit never uploads your file or your password to our servers. The encryption and decryption happen on your own device in your browser, so a confidential agreement, statement, or ID stays with you and your password is never transmitted or stored. That matters here more than anywhere: a password sent to someone else's server is a password you no longer control. You can confirm it — open your browser's network tab and watch, your file is never uploaded to our servers while you protect or unlock.

Frequently asked questions

Are my files uploaded to a server?

No. Encryption and unlocking run 100% in your browser. Your PDF and its password are never sent to our servers, so there is nothing for us to see, store, or leak.

What encryption does it use?

You can choose AES-256 (V=5, R=5), the modern standard supported by current PDF readers, or RC4 128-bit Compatible mode for older viewers. Both set a real open password, not a fake restriction.

Can it unlock a PDF if I forgot the password?

No. This tool removes encryption only from PDFs you can already open, so you must know the password. It does not crack or guess unknown passwords.

Will unlocking keep my text selectable?

No. To safely strip the encryption, each page is rasterized to an image during unlock, so the result looks identical but the text is no longer selectable or searchable. Keep your original if you need editable text.

What's the difference between the user and owner password?

The user password is required to open the PDF. The optional owner password controls permissions like printing and copying; if you leave it blank, it defaults to your user password.

Is there a file size limit and does it work on mobile?

You can protect or unlock PDFs up to 200 MB, and it runs in mobile browsers too. Because everything is local, very large files depend on your device's available memory.

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