Password Protect PDF Free — No Upload Required

Add password protection to your PDF for free. AES-256 encryption runs in your browser — nothing uploaded to any server.

Add military-grade AES-256 password protection to your PDFs without paying for Adobe Acrobat or uploading files to a third-party server. The encryption runs locally in your browser with zero-knowledge privacy — even we can't see your files.

Private — encryption happens in your browser

Drop PDF to password-protect

PDF • Max 200MB

🔒100% Private — Your files never leave your device. All processing runs locally in your browser.

How It Works

Add password protection to any PDF using AES-256 encryption — the industry standard used by banks and governments. The encryption process runs entirely in your browser using WebAssembly, so your PDF and password never leave your device.

Choose a strong password, confirm it, and download the encrypted PDF. Recipients will need the password to open the file. The original formatting, fonts, and images are preserved exactly.

Features

  • AES-256 encryption — military-grade security standard
  • Password-to-open protection prevents unauthorized access
  • Preserves all formatting, fonts, and embedded images
  • Handles PDFs up to 200MB
  • Zero-knowledge — your password never leaves your device
  • Compatible with all PDF readers (Adobe, Chrome, Preview)

Frequently Asked Questions

Yes — the tool uses AES-256 encryption, the same standard used by banks and governments worldwide.

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