Protect PDF with Password
Encrypt your PDF with strong password protection to prevent unauthorized opening and viewing.
Select PDF document to encrypt
Drop your PDF here to lock with a secure password
How to use Protect PDF in 3 easy steps
No software installation required. 100% free and runs smoothly on mobile, tablet, or desktop.
1. Select PDF File
Upload the document you want to secure with password encryption.
2. Set Strong Password
Type your secure password and confirm it.
3. Encrypt & Download
Save your password-protected PDF file.
Guaranteed Document Confidentiality
Your files stay on your machine. Client-side tools do not send your files to our servers.
Frequently Asked Questions
Everything you need to know about Protect PDF on HoudiniPDF.
Can anyone open the PDF without the password?
No. The file is encrypted using standard PDF security algorithms, so standard readers demand the password.
What happens if I forget my password?
Because we never store passwords or files on our servers, forgotten passwords cannot be recovered. Keep your password safe!
Is the password transmitted over the web?
No. The encryption takes place 100% inside your browser.
Can I remove the password later?
Yes! Use our "Unlock PDF" tool whenever you wish to remove the password restrictions.
Is this tool completely free?
Yes, 100% free with unlimited document protections.
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