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Password Protect PDF

Add a password to one PDF or several at once. Download encrypted copies that require your password to open.

  • AES-256 encryption Modern PDF password security
  • Multiple PDFs supported Protect a batch in one pass
  • Processed on your device Nothing uploaded to our servers

Upload PDF

or drop them here

Multiple files supported · PDF only · up to ~200 MB each

Password

Add PDFs in step 1 to continue.

AES-256 passwords are limited to 127 UTF-8 bytes (not character count). Multibyte characters use more than one byte. Passwords are never trimmed or normalized. Generate length is 8–127 and is saved in this browser.

Advanced options

Printing

Result

Your protected PDFs will appear here.

How it works

  1. Choose PDFs

    Select one file or a batch.

  2. Set a password

    Add your new password; permissions are optional.

  3. Download

    Save protected PDFs individually or together as a ZIP.

Frequently asked questions

Choose one or more PDFs, enter or generate a new password, then protect and download. Optional permissions and an owner password sit under Advanced.

No. Files and passwords are processed in your browser and are not uploaded.

Yes. The new password you set applies to every selected file in the batch. Download each protected PDF or all of them as a ZIP.

Yes, under Advanced. Choose what to allow in supported PDF readers. Enforcement varies by reader; the opening password still controls access to the document.

We cannot recover it. Keep it somewhere safe. Unlock PDF can remove protection later only if you still know the opening password.

Rewriting encryption can invalidate existing digital signatures or certification. You will see a warning when signatures are detected. The original file is preserved on your device.
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