Protect PDF
Password-protect your PDF files with encryption. Coming soon. We're building this the right way.
Add password protection to any PDF document.
Coming soon. Client-side encryption done right.
Coming Soon
We're building proper AES encryption for client-side PDF protection. We won't ship a tool that gives a false sense of security. When this launches, it will genuinely protect your documents.
Why the wait? The most popular browser PDF library (pdf-lib) does not support encryption. We're evaluating secure alternatives to ensure your passwords actually protect your files.
Meanwhile, try these alternatives:
- •Adobe Acrobat: Industry standard, full encryption support
- •LibreOffice: Free desktop app with PDF export and password
- •macOS Preview: File → Export as PDF → Encrypt
Two Types of PDF Passwords (Most People Only Know One)
When most people say "password-protect a PDF," they mean stopping someone from opening it. But PDFs actually support two completely different password types — and they do very different things.
| Password Type | What It Controls | Can They View the PDF? | Security Level |
|---|---|---|---|
| Open Password | Whether the file opens at all | No — completely locked | High (AES-256 encryption) |
| Permissions Password | What viewers can do (print, copy, edit) | Yes — can read, can't act | Medium (can be removed by tools) |
What this means for you: If the document is truly confidential, use an open password. If you just want to prevent printing or copying (for preview documents, for example), a permissions password is enough. For maximum protection, set both.
How to Choose a Strong PDF Password
A weak password makes encryption meaningless. Here's what actually matters:
Use 12+ characters mixing letters, numbers, and symbols
A 12-character password with mixed characters takes billions of years to brute-force with AES-256. "T4x-R3turn_2025!" is strong and memorable.
Send the password separately from the file
Email the PDF, then text or call with the password. If someone intercepts the email, they still can't open the file.
Use "password", "123456", or the recipient's name
These are the first things anyone would guess. Dictionary attacks crack common passwords in seconds.
Put the password in the same email as the PDF
"Please find attached the contract. Password is contract123." — you've just made the encryption worthless.
Need a strong password? Use our Password Generator to create one instantly.
When You Should (and Shouldn't) Encrypt PDFs
Protect when...
- Emailing financial data (payslips, tax returns, bank statements)
- Sharing contracts before signing
- Storing sensitive docs in shared cloud folders
- Sending HR documents to employees
- Distributing preview copies you don't want printed/copied
Skip encryption when...
- The document is already public (marketing brochures, menus)
- Recipients will need to print or fill in the form
- The PDF will be posted on a website for download
- You're archiving internally and everyone has access anyway
- The password will be more hassle than the content is worth
PDF Encryption vs Other Security Methods
| Method | Protects Against | Limitations |
|---|---|---|
| PDF open password | Unauthorised viewing | Useless if password is shared or weak |
| PDF permissions password | Printing, copying, editing | Can be removed with freely available tools |
| Watermark | Misuse of document (visual deterrent) | Doesn't prevent access or copying |
| ZIP with password | Unauthorised extraction | ZIP encryption is weaker than AES-256 PDF |
| Encrypted email (PGP/S/MIME) | Interception during transit | Doesn't protect the file at rest |
Best practice for sensitive documents: PDF open password (protects the file) + send password via a separate channel (protects the delivery). Add a watermark if the document might be forwarded.
Related PDF Tools
How to use this tool
Upload your PDF file
Set a strong password
Choose permission settings
Common uses
- Encrypting contracts and legal documents before emailing
- Password-protecting payslips, tax forms, and HR documents
- Restricting printing and copying on preview documents for clients
- Securing confidential reports stored in shared cloud folders
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