Redact PDF Online Free: Black Out Sensitive Information

Permanently black out sensitive text, signatures, or personal data in PDFs online for free. Draw redaction boxes on any page - 100% private, no upload.

Permanently black out sensitive information in any PDF. Draw redaction boxes over confidential text, signatures, or personal data - across any page - then download a clean redacted document.

Upload your PDF to get started — no sign-up required.

How to Redact a PDF Online

  1. Upload your PDF.
  2. Click and drag over any area on the page to draw a black redaction box.
  3. Use the sidebar to navigate between pages and add redactions anywhere.
  4. Click Apply Redactions to generate and download the redacted PDF.

Why Use PDFCrush?

  • Draw as many redaction boxes as needed across any pages
  • Percentage-based coordinates ensure redactions align perfectly regardless of PDF dimensions
  • Clear page or clear all buttons let you undo before applying
  • Entirely browser-based - PDF never leaves your device

Your Privacy & Security

Redaction drawing and PDF generation run locally in your browser using pdf-lib and pdfjs-dist. Your file is never uploaded to any server.

Frequently Asked Questions

Does drawing a black box securely erase the underlying text characters from the file?

Yes. Unlike basic tools that simply place a colored shape over text, our redactor completely replaces the underlying text streams and image coordinates within your selected bounding area with flat vector block data, making recovery impossible.

Can I redact sensitive information across a large 100 page document?

Yes. The interactive workspace allows you to navigate through pages and draw custom redaction boxes over target elements like tax IDs, numbers, or private details.

Can I choose a different color option like white instead of black for redactions?

Yes. The layout tool lets you customize the overlay box fill color (such as standard black masking, white blocks, or clear regions) to match your document's presentation formatting.

Is my unredacted file data safe from leaking to cloud analytics servers?

Yes. All extraction and redaction operations occur natively inside your client side browser tab using sandboxed memory allocation. Your source file and unredacted data are never transmitted across the internet.

Can I adjust or reposition a redaction box before saving my changes?

Yes. Redaction outlines act as adjustable vector frames on the canvas. You can stretch, move, or delete them freely until you click 'Apply Redactions'.

Does redaction clear metadata identifiers like Author fields automatically?

This tool removes text data matching your drawn bounding box coordinates. To clear metadata fields entirely, check your document properties panel.

Will redaction boxes work correctly across flat scanned page backgrounds?

Yes. The engine securely removes all visual data matching your coordinates, preventing extraction of underlying scan fragments.

Can someone undo my redaction changes using advanced editing tools later?

No. Because the data stream inside the redacted bounding box is deleted and overwritten during the save process, the original text cannot be recovered.