Lock PDF

Add a password so only the people you choose can open the document. Encrypted with 256-bit AES.

Drop a PDF here, or click to choose

The file you want to protect

Encryption runs on our server, so the file and password are uploaded over an encrypted connection. Both are deleted as soon as your download finishes, and the password is never stored.

Your processed file downloads automatically when it is ready.

HOW TO

How to password protect a PDF

A locked PDF asks for a password before it will open, in every reader on every device. It is the simplest way to send something confidential by email.

  1. 1

    Choose your PDF

    Drag the file in or click to browse. Anything you can open normally can be encrypted.

  2. 2

    Set a password

    Type it twice so a typo cannot lock you out of your own document. The strength indicator shows how well it would hold up.

  3. 3

    Download the locked file

    Press Lock and the encrypted copy downloads. Your original stays unprotected on your device, so keep it if you still need it.

USE CASES

When a document needs a lock

Anything you would not want read by whoever happens to see the inbox.

Payslips and statements

Send financial documents that stay unreadable if the email lands in the wrong place.

Contracts

Share an agreement with only the people who are meant to read the terms.

Medical records

Protect health information that has to travel by email.

Identity documents

Add a layer of protection when a form asks you to send a scan of your ID.

Internal reports

Circulate results or plans that should not spread beyond a specific group.

Client deliverables

Send finished work that only the paying client should be able to open.

TIPS

Choosing a good password

The encryption is strong. Whether the file is actually safe comes down to the password.

  • Length beats complexity. Several unrelated words are both stronger and easier to remember than a short string of symbols.
  • Never reuse a password you use elsewhere, since this one has to be shared with whoever receives the file.
  • Send the password separately from the document — by text or a call, not in the same email.
  • Write it down somewhere safe before you send anything. A forgotten password cannot be recovered by anyone, including us.
  • Avoid names, dates and anything guessable from the document itself.
  • Keep your unencrypted original. The locked file is a separate download, and you will want the plain copy for your own use.
FAQ

Questions, answered

How the encryption works and what it does and does not cover.

Still stuck?

Send us the details and we will take a look.

Get in touch

Upload the PDF, type the password you want, and download the protected copy. Anyone opening it afterwards has to enter that password. The file is encrypted with 256-bit AES.