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Password protect PDF

Add a password and control what readers may do.

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Supported: PDF

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About Password protect PDF

Set an open password so only the right people can read the file, and an owner password to restrict printing, copying and editing. Encryption is applied with AES-256.

  • AES-256 encryption
  • Separate user and owner passwords
  • Granular permission flags

How to password protect pdf

  1. 1

    Upload the document

    Any unprotected PDF.

  2. 2

    Set passwords

    Open password, owner password, or both.

  3. 3

    Choose permissions

    Allow or block printing, copying and editing.

A practical guide to password protect pdf

Choosing the right kind of password

Start by deciding what you are guarding against. If the goal is to keep the wrong people from reading a contract, tax form or medical record, set an open password and share it through a separate channel from the file itself. If instead the document can be read freely but you want to prevent tampering or unauthorized printing, use only an owner password with the matching permission flags. Many people set both: an open password for confidentiality and an owner password so that even authorized readers cannot alter the file. Match the protection to the actual risk rather than locking everything by reflex.

Passwords you can actually rely on

The most common mistake is a weak password that undermines strong encryption. Use a long passphrase, avoid names and dictionary words, and never reuse a password you already use elsewhere. Crucially, a forgotten open password cannot be recovered by anyone, including us, so save it in a password manager the moment you set it. When you send a protected file, deliver the password separately, by a phone call or a different app, rather than in the same email as the attachment, so a single intercepted message never exposes both.

Protecting as the final step in your workflow

Add the password last, once the document is truly finished. If you still need to sign, fill fields, add page numbers or merge in other files, do all of that first, because you would otherwise have to unlock the file to keep working. Applying several protected files at once is possible by adding a batch and giving them the same settings. If you later need to relax the restrictions on a document you own, the unlock tool removes protection when you supply the password. Keep an unprotected master copy in a safe place so you are never dependent on remembering the password to edit again.

Frequently asked questions

What is the difference between the user password and the owner password?
The user, or open, password is what someone must type to view the document at all; without it the file will not display. The owner, or permissions, password leaves the file readable but locks down actions like printing, copying or editing. You can set one, the other, or both, and using two separate passwords lets you share reading access while still controlling what recipients can do.
How strong is the encryption?
Protection is applied with AES-256, the same standard trusted for sensitive documents generally. The real strength depends on your password: a long, unique passphrase is what makes AES-256 worthwhile, while a short common word can be guessed no matter how strong the cipher. Store the password in a manager rather than reusing an easy one.
I only want to stop editing, not viewing. Can I do that?
Yes. Set just an owner password and leave the open password blank. Anyone can open and read the file, but the permission flags you choose will block editing, printing or copying in compliant readers. Note that these flags govern PDF software; they cannot stop someone from photographing or screenshotting what is on screen.
What happens to my file and password on your side?
The document is encrypted during the session and then deleted automatically from the servers, and the password is not stored anywhere, so make sure you record it yourself. There is no account to sign up for, and your original unprotected file stays untouched on your device.

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