Encrypt / Decrypt PDF

Protect PDF with password or remove password protection

Drag & drop a PDF file here, or click to browse

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Maximum file size: 128 MB

All processing happens locally in your browser. Your files never leave your computer.

Password Protect PDF Free — Secure AES-256 Without Paying

Add professional-grade password protection to any PDF — entirely free. AES-256 encryption, browser-side processing, no daily limits, no watermarks, no sign-up. Whether you secure one document or one hundred, our tool is ready. Replaces paid alternatives like Adobe Pro for this specific task.

100% FreeNo UploadNo Sign-up100% Free, No Limits

How to Use

Drop PDF: Drag any PDF in. Multi-page documents supported. The tool shows file size and confirms the PDF is ready for encryption.
Set Strong Password: Enter a password. We recommend 12+ characters with mixed case, numbers, and symbols. Password length matters more than complexity — passphrases like 'correct-horse-battery-staple' are excellent.
Optional Restrictions: Decide whether to restrict printing, copying, or editing. For maximum compatibility, leave restrictions off and rely on the open password alone.
Encrypt: Click 'Encrypt'. Your PDF is encrypted in your browser with AES-256. The output downloads as a new file. Process 1, 5, or 100 documents — no usage limits.

Why Choose This Tool

100% Local Processing: Files are processed entirely in your browser using JavaScript — never uploaded to any server.
No Limits: No file count or file size restrictions. Process as many files as your device can handle.
No Sign-up: Free forever, no account needed, no email required. Open the page and start.
Private by Design: Nothing is sent to any server. Close the tab and your files are gone forever.

Common Questions

Can I password protect a PDF for free?

Yes — our PDF Encrypt tool is 100% free with no sign-up, no daily limits, no watermarks. Drop your PDF, set a password, click 'Encrypt'. The encrypted PDF downloads immediately. We use AES-256, the same encryption standard as paid tools like Adobe Pro.

Is this as secure as Adobe Pro?

Yes for the encryption itself. Adobe Pro uses the same AES-256 standard that we use. The difference: Adobe offers additional features (digital signatures, certificate-based encryption, redlining tools) that we don't. For password-based protection, our output is identical in security strength.

How is this free without ads or selling my data?

We use opt-in non-intrusive advertising on some pages, and premium sponsored positions. We never sell user data, never upload files (everything is browser-side), and never limit usage to force a paid tier. PDF protection is a basic document utility — it should be free for everyone.

Will my PDFs be uploaded?

No. Encryption runs entirely in your browser via pdf-lib + Web Crypto API. Your PDF and your password stay on your device. Only the encrypted output saves locally.

Can I protect many PDFs at once?

Yes — drop multiple PDFs and the tool processes them sequentially. You get a ZIP of encrypted PDFs (each with the same or different passwords, your choice). No limit on batch size other than your device memory.

What if I forget the password?

Recovery is impossible by design — AES-256 with a strong password cannot be brute-forced. If you forget the password, the encrypted PDF is effectively inaccessible. Always store passwords in a password manager (1Password, Bitwarden, LastPass) or in a secure written record.

Other Use Cases for PDF Encrypt

Encrypt PDF with Password — AES-256 Browser-Side Protection

PDF Encrypt → / en/tools/pdf-encrypt/encrypt-pdf-password/

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Sponsored tools for this use case

NordPass

After password-protecting your PDF, store the password in NordPass so you never have to remember it yourself.

Strong PDF passwords are unusable if they live in a notes app — a password manager keeps them encrypted and autofill-ready.

Learn more