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Protect PDF

Protect your PDF with a password

Drop your PDF file here

or click to browse - up to 100 MB per file

Add a PDF file first

Add a PDF file first

Add a PDF file first

Practical guides
How to Redact a PDF Safely Before You Share ItHow to Sign a PDF Fast on Mobile and Desktop
How to use this tool well

How to use this tool well

Protect PDF

Add password protection to PDF files and control access permissions for printing, editing, and copying.

Use one clean processing pass, then do a quick QA review before you share the result.

Good fit for

  • Secure confidential contracts before sharing.
  • Restrict editing or copying on distributed PDFs.
  • Set strong encryption for compliance-sensitive files.

Typical workflow

  1. 1. Upload your file to the Protect PDF tool.
  2. 2. Choose processing options to match your output needs.
  3. 3. Process and download the result when ready.

Check before you share

  • Review first, middle, and last pages after processing.
  • Check text, tables, signatures, or stamps at 100% zoom.
  • If something looks off, change one setting and rerun once.

Related SentryPDF tools

Unlock PDF

Unlock password-protected PDFs when you have valid access credentials. Remove restrictions for normal processing.

Sign PDF

Place visible signature appearances and initials on PDF pages (typed or drawn; not certificate-based digital signatures).

Redact PDF

Permanently remove content inside selected redaction boxes and export a sanitized PDF copy for sharing.

FAQ

What encryption standard does SentryPDF use?

SentryPDF applies AES-based encryption compatible with the PDF specification. The encryption is applied by a server-side processor and the output is a standard password-protected PDF.

Can I set different permissions like printing or editing?

Yes. You can independently allow or restrict printing, editing, copying text, and adding annotations. These permissions are enforced by the PDF viewer when the file is opened.

Can I protect a PDF that is already password-protected?

No. Remove the existing password first using the Unlock PDF tool, then apply your new password and permissions.

What happens if I forget the password after protecting?

SentryPDF does not store passwords. If you lose the password, you will not be able to open the protected file. Store your password securely before sharing the protected PDF.

Is the file kept on your servers after protection?

No. The protected PDF is available for download for a short window and then automatically deleted. Download it immediately after processing.

Explore more PDF tasks

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Add a PDF file first

Add a PDF file first

Related guides for this tool

Open tool: Protect PDF

Step-by-step guides

How to Redact a PDF Safely Before You Share ItHow to Sign a PDF Fast on Mobile and DesktopAll guides

Workflow guides

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