How to Password-Protect a PDF Before Sharing
Password protect PDF files before sharing them to help keep sensitive documents secure. Adding a password can prevent unauthorized people from opening your PDF and viewing its contents.
What kinds of PDFs to protect
Anything containing personal data: medical records, tax documents, ID scans, signed contracts. Anything containing financial data: bank statements, salary information, business financials. Anything you wouldn't read out loud in a coffee shop.
Password best practices
Use a passphrase, not a word: 4-5 random words is harder to brute-force than a single 'strong' word with substitutions. Don't reuse passwords across documents — if one leaks, only one document is compromised. Send the password through a different channel from the document itself.
How to apply protection
Open Protect PDF, upload your document, enter a password, click Protect PDF. The protected file downloads, and any PDF viewer will prompt for the password before opening.
Encryption strength
PDFPuddle applies pdf-lib's metadata-level protection, which prevents casual access but isn't equivalent to AES-256 encryption. For maximum security on highly sensitive documents, use Adobe Acrobat with AES-256 encryption or encrypt the file at the filesystem level (e.g. with 7-Zip's AES-256 mode).