100% Private
Your PDF never leaves your device. All encryption is performed inside your browser, no files are uploaded or stored anywhere.
Protect PDF with Password
Add password protection to any PDF file in seconds, fully private, encrypted entirely inside your browser.
Guide
How to Password-Protect a PDF
1
Upload Your PDF
Drag and drop or choose any PDF file from your device.
2
Set a Password
Type a strong password to lock the PDF.
3
Download the Protected File
Click Protect and download the encrypted PDF instantly.
Lock Sensitive PDFs With Real Encryption
Sending tax records, contracts, or medical documents over email needs more than a hopeful tag in the subject line. The protector applies AES-256 encryption that every modern PDF reader respects.
Used by lawyers shipping case files, accountants emailing tax returns, and HR teams sending offer letters that must stay confidential.
Benefits
Why Use This PDF Protector
AES-256 Encryption
The tool uses the industry-standard AES-256 encryption algorithm in your browser, producing a protected PDF that is compatible with Adobe Acrobat and all major PDF readers.
Instant Processing
Most PDFs encrypt in under a second. The original content, layout, and text layers are preserved exactly, only the access protection changes.
Permissions Control
The protected PDF restricts copying, editing, and annotations by default, giving you control over how recipients can interact with the document.
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FAQ
Frequently Asked Questions
Common questions about PDF password protection.
Is my PDF safe to process with this tool?
Yes. The tool runs entirely in your browser using JavaScript. Your PDF is read from your device memory and the encrypted version is generated locally. No file data is ever sent to a server or stored online.
What encryption standard does this tool use?
The tool uses AES-256 encryption which implements AES-256 encryption, the same standard used by Adobe Acrobat. The resulting PDF is compatible with all modern PDF readers including Adobe Acrobat, Preview on macOS, and browser-based viewers.
Can the password be recovered if I forget it?
No. AES-256 encryption cannot be reversed without the correct password. If you lose the password, the document will be permanently inaccessible. Store your password in a password manager or secure location before protecting important files.
Can I protect a PDF that is already password-protected?
No. If a PDF already has encryption applied, browser PDF tool cannot re-encrypt it. Use the Unlock PDF tool first to remove the existing password, then use this tool to apply a new one.