DJToolsPDF · by DJAI AcademyProtect PDF
Password Protect PDF with AES-256
Password protect a PDF in your browser with AES-256 encryption and control printing, copying, editing, and form permissions.
Start using tools for freeDJToolsFree PDF Tool SetPDF workspace
Password Protect PDF with AES-256
Secure a PDF with a password and document permissions.
AES-256 · Keep this password safe. DJAI cannot recover it.
HOW TO
How to password protect a PDF with AES-256
Secure a sensitive document with a password and control printing, copying, editing, and form filling. DJAI never receives the password.
- 01
Select a PDF and create a strong password
- 02
Choose the permissions available to readers
- 03
Download the encrypted PDF and store the password safely
Private by design
Your PDFs, images, and passwords exist only in your browser memory. DJAI and Siamese Cat Dev do not receive, store, or view them. The data disappears when you close or refresh this page.
From documents to business systems
Need a document portal or workflow for your company?
DJAI and Siamese Cat Dev build websites, web applications, document systems, CRM platforms, automation, and AI workflows around real business processes.
Build your own tool
Learn Vibe Coding and turn a workflow into a product
Learn the path from idea and planning to building and launching websites, applications, and automation with AI.
Explore the course
Built with intention by
Siamese Cat Dev
Created with intention by Siamese Cat Dev. Siamese Cat Dev is a product designer, project manager, and software development partner with nearly 10 years of experience building digital products for real businesses. He is also a student at DJAI Academy and a development/training partner who helps transform ideas into usable products.
Meet the builderFREE PDF TOOLS
Free PDF tools built around privacy
DJTools handles everyday document tasks without installing software or creating an account. It is designed for students, educators, freelancers, small businesses, and teams that do not want to send documents to an external conversion server.
Questions about DJTools PDF
Are these PDF tools really free?+
Yes. All core tools are free, with no account, watermark, or charge after processing.
Where are my PDF files uploaded?+
Nowhere. Reading, editing, and creating the result happens in your browser on your device.
Does PDF compression reduce quality?+
Light keeps the document structure. Recommended and Strong render new pages to reduce size, which can flatten forms and make text non-searchable.
Can I use the tools on a phone?+
Yes, in a modern browser. Very large PDFs or documents with hundreds of pages work better on a computer with more memory.