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Protect

Protect PDF

Encrypt a PDF with an opening password. Runs on this device

Add your files

Your documents are held only in your active browser tab.

PDF files only

Choose a local file to begin.

No upload queue

Your documents are held only in your active browser tab.

No account

There is no sign-in, batch quota, or server file store.

Clear when done

Use the clear control to release task data immediately.

Guide

How to use Protect PDF

Encrypt a PDF with an opening password using AES-256.
InputOne PDF, password, and matching confirmation.
OutputOne encrypted PDF.
PrivacyProcessed only in this browser tab.

About password protect PDF

Encrypt a PDF with an opening password using AES-256. Protect a document that needs an opening password before it can be viewed, such as a sensitive statement or file that must be sent to a specific recipient.

Protection applies AES-256 encryption with a user password of at least four characters, set alongside a permission profile that allows printing while disallowing copying and modification. There is no separate owner password and no way to adjust individual permissions. The password exists only in your browser while you type it, which has an important consequence: a forgotten password cannot be recovered by us or by anyone else, because it was never stored or transmitted. Permission flags are advisory, honoured by compliant readers and ignorable by others, whereas the encryption itself is real.

How PDFolio helps you password protect PDF

Enter and confirm an opening password, then PDFolio creates a separate encrypted copy using AES-256. Use a password you can share safely and store it separately from the protected file, since PDFolio cannot recover it.

Encryption controls who can open the file; it does nothing about what the file says. If specific content should not be readable by someone who does have the password, that content has to be removed before protection is applied. Unlock PDF reverses this operation when you know the password.

Before you download

The output requires its opening password in compatible viewers. The current export allows printing but restricts copying and modification. Protection improves control of the copy you share, but someone who can view a document can still take a screenshot or re-create information.

When the result is ready, download it immediately and open it in your usual PDF viewer to make a final check. You can then use Clear task data to release temporary file references from this browser tab. PDFolio does not create an account, cloud folder, or server-side document history.

A private way to password protect PDF

PDFolio handles the selected files in the active browser tab. A Web Worker on your device performs the PDF task so the interface can remain responsive; document bytes are not sent to a PDF processing server, upload queue, account database, or advertising platform.

Steps

  1. Add a PDF.
  2. Enter and confirm an opening password.
  3. Process and store the password safely before sharing the file.

Good to know: PDFolio cannot recover forgotten passwords. Encryption is applied only to the downloaded copy.

Frequently asked questions

What PDF encryption does PDFolio use?

The protected export uses AES-256 encryption.

Can PDFolio recover a forgotten PDF password?

No. Store the password safely before sharing the protected file.

Can I print a protected PDF?

Yes. The current export allows printing while restricting copying and modification.

Does password protect PDF change my original file?

No. PDFolio creates a new file for download. Your source file remains unchanged on your device.