How do I password protect a PDF for free?

Drop your PDF into Morphix, pick a password, and click Protect. Your file is encrypted with AES-256 directly in your browser — no upload, no signup, no watermark.

Is encrypting my PDF online safe?

Morphix runs 100% in your browser using the WebCrypto API. Your PDF and password never leave your device, never touch a server, and have no file-size limit.

What encryption does Morphix use?

AES-256-GCM with a PBKDF2-derived key (250,000 iterations) — the same encryption standard used by banks and governments. Far stronger than the legacy 40-bit RC4 password some old PDF tools still use.

How do I open the protected PDF later?

Open the Morphix Vault page, drop the .morphix file in, enter your password, and the original PDF is restored. The decryption also runs entirely in your browser.

Can I unlock a PDF if I forget the password?

No. Strong AES-256 encryption with a properly chosen password is mathematically infeasible to brute-force. Store your password in a password manager before encrypting important files.

Does Morphix work offline?

Yes. Once the page is loaded, you can disconnect from the internet — all encryption happens locally in your browser.

Morphix

AES-256 · 100% in your browser

Password Protect PDF

Add a strong password to any PDF in seconds. Morphix encrypts your file with AES-256-GCM directly in your browser — no upload, no signup, no file-size limit.

AES-256-GCM
Files stay local
No size limit
No signup

AES

PDF

SHA

KEY

GCM

256

Drop a PDF here or click to choose

Your file never leaves your browser.

—

Outputs a .morphix file. Open it any time at Morphix Vault with the same password.

How to password protect a PDF

1. Drop your PDF into the box above — it stays on your device.
2. Choose a strong password (12+ chars with a mix of letters, numbers, symbols).
3. Click Protect PDF — Morphix encrypts the file with AES-256-GCM in your browser.
4. Download the protected file and share it. Only people with the password can open it.

Why Morphix is safer than legacy PDF passwords

Many free "password protect PDF" tools still use the original PDF 1.x security handler — 40-bit RC4 — which can be brute-forced on a laptop. Morphix uses AES-256-GCM with a key derived via PBKDF2-SHA-256 (250,000 iterations and a per-file random salt). It's the same encryption standard governments and password managers use, and it runs entirely client-side so your PDF never touches a server.

Frequently asked questions

Is it really free?

Yes — no signup, no paywall, no watermark, no file-size limit.

Do you upload my PDF?

Never. Everything runs in your browser via the WebCrypto API. You can disconnect from the internet before encrypting.

What encryption is used?

AES-256-GCM with PBKDF2-SHA-256 key derivation (250,000 iterations + random salt + random IV).

How do I open the protected file later?

Drop the .morphix file in Morphix Vault and enter your password — the original PDF is restored.

Can I recover a forgotten password?

No. A strong AES-256 password is mathematically infeasible to brute-force, so store yours in a password manager.

Does it work on mobile?

Yes. Any modern browser on iOS, Android, Windows, macOS or Linux.

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