Password protect a PDF

Add a password to a PDF so it cannot be opened without it. Upload your file, choose a password, and download the encrypted PDF with strong AES-256 protection. Your file is processed on our secure server and deleted right after.

How to protect pdf

1. 1Upload the PDF you want to protect.
2. 2Choose a password.
3. 3We encrypt the PDF with AES-256.
4. 4Download your password-protected PDF.

When to use this tool

• You're emailing a contract, tax document, or financial statement and want it locked to the intended reader.
• A company policy requires sensitive PDFs to be password protected before they're shared.
• You're storing a personal document and want an extra layer of protection if the file is ever lost.
• You need to send a document to a client but don't want it forwarded without a password.
• You're archiving old tax returns or statements and want them locked in case the storage is ever accessed by someone else.
• You're sending a document over email, which isn't always a fully secure channel on its own.

Tips for a better result

• Share the password separately from the file, like by text instead of the same email.
• Write the password down somewhere safe; there is no way to recover it if it's lost.
• Use Unlock PDF later if the recipient no longer needs the password requirement.
• Protect after you've finished editing, since you'll need to unlock it again to make further changes.
• Avoid reusing the same password for every document; a unique one limits the damage if it's ever exposed.

Privacy: what happens to your file

This tool uploads your file to our server, because PDF encryption needs a full document engine that a browser can't run. We write it to a temporary folder to process it, then delete that folder immediately after your download is ready, whether the job succeeds or fails. We don't keep a copy or share it with anyone.

Protect PDF is one of 34 free organize-category tools on fillable.ca. It pairs well with unlock pdf, compress pdf and watermark pdf for a complete document workflow — see the full tools listfor everything else that’s free to use.