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Security Apr 7, 2026 Tools360 Team

Protect PDF with Password — AES-256 Encryption Guide

Learn how to password-protect your PDF with military-grade AES-256 encryption. Best practices for Aadhaar, salary slips, and business documents.

Tools360 uses AES-256 encryption — the same standard used by banks and the Indian government for securing sensitive data. This is the strongest encryption available for PDF files.

When to protect your PDF: Before emailing Aadhaar or PAN copies, before sharing salary slips with banks, before sending business proposals to clients, and before uploading sensitive documents to cloud storage.

Choosing a strong password: Use at least 8 characters combining uppercase, lowercase, numbers, and symbols. Avoid using your date of birth or phone number as the password.

User password vs Owner password: The user password is required to open the document. The owner password controls permissions (printing, copying, editing). Tools360 lets you set both separately.

Permissions you can control: Allow printing but prevent copying text, allow reading but prevent editing, allow accessibility tools for visually impaired users.

Sharing protected PDFs: Always share the password through a different channel than the document. If you email the PDF, share the password via WhatsApp or SMS.

For Aadhaar: UIDAI recommends protecting your Aadhaar PDF with a password before sharing. The default password for UIDAI-downloaded Aadhaar is the first 4 letters of your name (uppercase) + birth year.

Remember: If you forget the password, there is no way to recover it. Keep a record of passwords for important documents in a secure password manager.

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