Protect PDF — Password-Encrypt & Restrict Access, 100% In-Browser
Lock down your PDFs with a password and fine-grained usage rules without uploading a single byte. Set a password to open the file, add an owner password for full control, and restrict printing, copying, editing, annotation and more. Every document is encrypted with AES-256 — the strongest standard PDF security — and the encryption runs locally in your browser, so your document and passwords never leave your device.
Frequently Asked Questions About Protecting PDFs
How does the PDF protector work?
Drop in any PDF and choose your settings: a password to open the file, an optional owner password and the actions you want to allow (printing, copying, editing and more). The document is then encrypted locally with AES-256 and a protected copy is ready to download.
Can I restrict printing or copying without a password?
Yes. Turn off the "Require password to open" toggle and only set the allowed actions. The file will still open freely, but the restrictions you choose will be applied to it.
Is AES-256 compatible with my PDF reader?
Yes. AES-256 is the modern standard and opens in virtually all current readers (Adobe, Preview, Chrome, Edge, mobile apps). Older files use weaker 128-bit or RC4 security, but everything new is produced with AES-256 for maximum protection.
Does protecting change my original file?
No. A brand-new, encrypted PDF is produced and your original file stays untouched on your device.
What should I do if my PDF is already password-protected?
Use the Unlock PDF tool to remove the existing protection first, then come back here and protect it with your own settings. A file can only carry one layer of password protection.