Protect PDF
Encrypt a PDF with a new password, configurable permissions, and an exact verified output preview.
- AES-256 encryption
- Password strength check
- Document permissions
- Exact encrypted-output preview
- Verified before download
Upload a file and run the tool.
Password protection with explicit encryption and permission controls
Create a new encrypted PDF copy that requires the chosen open password before pages can be viewed. AES-256 is the default, while AES-128 is available for older-reader compatibility.
Optionally restrict printing, copying, editing, annotations, form filling, accessibility extraction, and page assembly with a separate permissions password so the normal open password does not grant owner access.
How to protect a PDF
- Choose or drop one PDF up to 32 MB and enter its current password if it is already encrypted.
- Enter and confirm the new open password, then review its strength indicator.
- Keep AES-256 or choose AES-128 for compatibility with older PDF software.
- Optionally restrict document actions and enter a different permissions password when any restriction is enabled.
- Protect the PDF, inspect a page rendered from the actual encrypted output, and download the verified file.
Verify security and page structure before download
- Use native AES-256 or AES-128 PDF encryption without requiring an office-conversion container.
- Reject missing and mismatched passwords, overlong UTF-8 passwords, and unsafe shared open and permissions passwords.
- Reopen the generated file with the new password and verify encryption, page count, dimensions, and rotation.
- Render the exact encrypted output for post-generation page-by-page preview instead of showing a simulated security state.
- Keep passwords out of session metadata and API responses while temporary inputs and outputs expire automatically.
Protect PDF FAQ
Is the final preview rendered from the protected file?
Yes. The output preview opens the actual generated PDF with the new password and renders the selected encrypted-output page.
Which encryption should I choose?
AES-256 is the recommended modern default. AES-128 is available when older PDF software must open the file.
Why is a separate permissions password required?
It keeps the normal open password from also acting as the owner password when printing, copying, editing, or other actions are restricted.
Will every PDF viewer enforce permissions?
No. PDF permissions are viewer-enforced controls and can be ignored by non-compliant software. The open password still provides the encryption barrier.
Can an already protected PDF be processed?
Yes. Enter its current password first, then choose the new encryption, password, and permissions.
What happens to digital signatures?
Encrypting and rewriting the PDF changes its bytes, so existing digital signatures will no longer validate.
Help us improve this tool
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