Redact PDF file

Permanently remove sensitive content by covering areas with black boxes.

or drop PDF file here

Supports single PDF • 100% Local process in your device

How to Redact PDF Online

Securely remove sensitive information from your PDF documents in three simple steps, with 100% local processing to protect your privacy.

1

Upload your PDF

Click the Select PDF File button or drag and drop your document. In an era where cloud AI models scrape data, CedarPDF processes your file entirely offline in your browser — nothing is uploaded to any server.

2

Draw Redaction Boxes

Navigate through your pages and drag your mouse over any areas you want to permanently remove. Black boxes will appear to cover the selected areas.

Use the Undo, Clear Page, or Clear All buttons to adjust your selections before finalizing.

3

Apply & Download

Once satisfied, click Apply Redactions. Our tool will permanently burn the black boxes into the PDF, physically destroying the underlying data so it cannot be recovered by AI OCR or any other tool.

Download your secure, redacted file instantly. All data within the covered areas is permanently removed at the binary level.

Why Choose CedarPDF for Redaction?

100% Private & AI-Proof Security

Unlike cloud-based converters that upload your files to servers (where they risk being scraped by AI crawlers or used for model training), CedarPDF processes everything 100% locally in your browser. Your sensitive documents never leave your device, ensuring complete privacy and zero-knowledge security.

Permanent Data Removal (Defeats AI OCR)

We don't just place a visual black rectangle over text. CedarPDF permanently removes the underlying binary content. Once applied, the redacted information cannot be recovered, copied, or extracted by advanced AI OCR tools, guaranteeing true security.

Completely Free & Unlimited

No hidden fees, no email or registration required, and no daily limits. Redact as many PDFs as you need, regardless of file size or page count. Enterprise-grade privacy protection, completely free.

High-Quality Output

Preserve the original layout and quality of your document. Non-redacted text remains sharp, searchable, and selectable, ensuring your final PDF looks professional while keeping your secrets safe.

When Do You Need to Redact PDFs?

From students to professionals, CedarPDF helps people protect sensitive information effortlessly. Here are some common scenarios:

For Students & Researchers

Protect Academic Privacy

  • Redact personal information (name, student ID) from thesis submissions for anonymous review.
  • Remove sensitive grades or personal notes from shared academic transcripts.
  • Redact reviewer comments or confidential annotations before sharing research papers.
  • Best of all: It's completely free for unlimited student use!
For Professionals & Business

Secure Business Documents

  • Redact sensitive contract terms, pricing, or financial figures before sharing with external parties.
  • Remove confidential employee information, salaries, or SSNs from HR documents.
  • Redact sensitive legal information, party names, or case details from court filings.
  • Best of all: Your confidential documents never leave your computer.
For the AI & Big Data Era

Protect Data from AI Scrapers

  • Prevent AI Training: Ensure your sensitive documents are never uploaded to cloud servers where they could be scraped and used to train generative AI models.
  • Defeat AI OCR: Our redaction physically removes underlying data, meaning even advanced AI Optical Character Recognition cannot recover the hidden text.
  • Zero-Knowledge Processing: 100% client-side execution guarantees that no third-party API or AI agent ever has access to your private information.
  • Best of all: Enterprise-grade privacy protection, completely free and directly in your browser.

Frequently Asked Questions