● 100% In-Browser Memory • Zero Server Uploads

Protect PDF with AES-256 Encryption

Apply military-grade AES-256 bit password encryption and restrict printing, content extraction, and form field alterations.

Select PDF File or Drag & Drop Here

Files are processed entirely in local device RAM. Supported: .pdf

Quick Answer & Overview

Protect sensitive documents with AES-256 encryption. CrispPDF generates cryptographically secure initialization vectors in browser memory, enforcing user authentication and permissions before viewing.

How to Use Protect PDF

1 Select or drop your PDF document directly into the tool workspace.
2 Configure your preferred options or let CrispPDF optimize automatically.
3 Click Process to run the operation instantly inside your browser RAM and save your file.

Technical Specifications

Architecture WebAssembly (WASM)

Privacy Guarantee Zero Server Uploads

Max File Size 100 MB

Standard ISO 32000-1

Frequently Asked Questions

What encryption standard is applied to my PDF?

We apply standard ISO 32000-compliant 256-bit AES encryption compatible with Adobe Acrobat, Apple Preview, Google Chrome, and iOS/Android PDF readers.

What is the difference between a Document Open password and a Permissions password?

The Document Open password prevents unauthorized people from opening and reading the file. The Permissions password allows people to read it, but prevents printing, text copying, or editing.

Will the password protection work on all devices without installing software?

Yes. AES-256 encryption is natively supported by all standard PDF viewers across macOS, Windows, Linux, iOS, and Android.