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Encrypt PDF Online Free – Password Protect PDF | MultiToolHub

🔒 Encrypt PDF

Password-protect your PDF with real 128-bit RC4 encryption — 100% free, runs in your browser, no uploads needed.

🔐 RC4-128 Encryption
🖥️ 100% Browser-Based
🚫 No Upload Required
📱 Mobile Friendly
⚡ Instant Download
🆓 Free Forever
📄

Drop your PDF here

or click to browse from your device

📑
🔑 Password Settings
🛡️ Document Permissions
 
Encrypting…
⬇️ Download Encrypted PDF

Encrypted in your browser — your file never left your device.

🖥️

100% In-Browser

Your file is never sent anywhere. All encryption happens locally on your device.

🔐

Real RC4-128

Standard PDF encryption algorithm. Requires password to open in any PDF viewer.

⚡

Instant Result

PDFs encrypt in seconds and download immediately — no waiting.

🔓

Permission Control

Restrict printing, copying, editing, and more inside the encrypted PDF.

📖 How to Encrypt Your PDF – Step-by-Step

  1. 1

    Upload Your PDF

    Drag and drop your PDF into the upload box, or click to browse your device.

  2. 2

    Set a Strong Password

    Enter a password — anyone opening the PDF will need this exact password.

  3. 3

    Choose Permissions

    Toggle which actions are allowed on the encrypted file: printing, copying, editing, etc.

  4. 4

    Encrypt & Download

    Click "Encrypt PDF". Your file is encrypted entirely in-browser — download instantly.

❓ Frequently Asked Questions

No. Everything runs in your browser. Your PDF never leaves your device — there is no server, no cloud, no data retention.
This tool uses standard PDF 1.4 RC4-128 encryption, recognized by Adobe Acrobat, Adobe Reader, Foxit, macOS Preview, Okular, and most modern PDF viewers. Always test with Adobe Reader for definitive enforcement.
There is no recovery option — this is by design. Please store your password in a secure password manager before encrypting.
No enforced limit. Processing happens in browser memory; very large files (100 MB+) may take a few extra seconds depending on your device.
RC4-128 (PDF 1.4 standard) is universally supported by all PDF viewers including older ones. AES-256 requires PDF 1.7+ and may not be recognized by some viewers. For document compatibility, RC4-128 is the most reliable choice.

Why Encrypt Your PDF Files?

PDF encryption is the most reliable way to protect sensitive documents from unauthorized access. Whether you're sharing financial reports, legal contracts, medical records, or confidential business plans — encrypting your PDF ensures only authorized recipients can open it.

RC4-128 PDF encryption is a globally recognized standard supported by every major PDF viewer. When a viewer opens an encrypted PDF, it prompts for the password before revealing any content, making the document completely unreadable without it.

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