How to Password-Protect a PDF (AES-256, Free)
Encrypt a PDF with a password before you send it, control printing and copying, and share the password safely.
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Payslips, bank statements, contracts and ID copies travel by email every day. A password-protected PDF means that if the email is forwarded, misdirected or the inbox is compromised, the document still can't be opened.
How to password-protect a PDF
- Open the free Protect PDF tool.
- Choose your PDF and enter a password (twice).
- Choose what people can do after opening it — print, copy text, edit.
- Click Protect & download.
The file is encrypted with AES-256 in your browser before you download it. Neither the file nor the password is ever uploaded.
Open password vs owner password
| Password | What it does |
|---|---|
| Open (user) password | Required to view the document at all |
| Owner (permissions) password | Controls printing, copying and editing restrictions |
If you leave the owner password blank, the tool generates a random one so permissions can't easily be lifted. Note that permission restrictions depend on the viewer respecting them — the open password is the real protection.
Choosing a good password
- At least 12 characters — a passphrase like
Mango-Harbour-27-Lanternis strong and easy to type. - Don't reuse your email or banking password.
- Generate one with the Password Generator.
Share the password separately
Email the file and send the password another way — WhatsApp, SMS or a phone call. If both travel in the same email, anyone who gets the email gets the document.
Compatibility
AES-256 PDFs open in Adobe Acrobat Reader, Chrome, Edge, Firefox, macOS Preview and modern mobile viewers. Very old readers may not support it.
Forgot the password?
There's no recovery — that's the point of encryption. Keep the password in a password manager.
Why browser-based PDF tools are safer
Most online PDF sites upload your file to their servers. Pyalm's PDF tools run entirely in your browser — the file is read, processed and saved on your own device and never sent anywhere. That matters for contracts, invoices, bank statements and ID documents.
Security beyond documents
Encrypting files protects data in transit. Verifying who is on the other end protects your business from fraud. FaceTrust adds self-hosted face matching, liveness detection and ID document checks to onboarding and access control.
Related free tools
Protect PDF | Unlock PDF | Password Generator | Watermark PDF | All free tools