What is PDF redaction?

PDF redaction permanently removes sensitive text, images, or metadata from a PDF so the underlying content cannot be recovered. Unlike a black highlight, true redaction overwrites the page object stream and strips hidden layers, making it the standard for legal discovery, HIPAA, and GDPR compliance.

Redact PDF — Remove Sensitive Information from PDF

Redact PDF files online free. Auto-detect SSN, email, phone, and credit card patterns. Permanent redaction for HIPAA compliance. No signup.

About Redact PDF

Redact PDF permanently blacks out sensitive text, images, and metadata from any PDF — names, social security numbers, account numbers, medical diagnoses, attorney-client privileged text — using PDF-lib's content stream rewriting engine, entirely in your browser. Unlike other tools that just draw a black rectangle on top of the text (leaving the underlying characters readable in the PDF structure), this tool replaces the selected content stream operators with blank fills, then strips the original text runs from the page. The redacted areas are permanently gone from the PDF bytes, not just visually hidden. The selection interface uses PDF.js to render the page, then overlays a coordinate-mapped click-and-drag region selector. When you select a region, the tool calculates the corresponding PDF coordinate space (accounting for rotation, scale, and the y-axis flip between screen and PDF coordinate systems) and removes all text rendering operators within that region. Images can also be redacted by replacing the image XObject with a solid black rectangle of identical dimensions.

The difference between "visually redacted" and "permanently redacted" is legally critical. Adobe Acrobat's free Reader lets you draw black boxes but leaves text in the PDF byte stream — discoverable with a text editor. This tool overwrites the PDF content stream: selected text glyphs are replaced with empty operators, and the original text strings are not present in the output file byte-for-byte. Metadata scrubbing removes the Author, Keywords, Creator, and Producer fields that often contain PII. The output passes PDF forensic analysis as permanently redacted.

Key Features

Permanent content-stream redaction — selected text operators replaced with blank fills, not covered by a box overlay
Click-and-drag region selection on a PDF.js live preview — select any rectangular area on any page
Image redaction — replaces image XObjects within the selected region with a solid black rectangle
Metadata scrubbing — strips Author, Keywords, Creator, Producer, and custom metadata fields that often contain PII
Multi-page support — add regions on any page; all redactions apply in one processing pass
Redaction review — shows a list of all marked regions before finalizing so you can remove incorrectly marked areas
Visible redaction marks — outputs a solid black box at each redaction location (per legal redaction standards)
Client-side PDF-lib processing — no upload, no server, files up to 100 MB

How to Use Redact PDF — Remove Sensitive Information from PDF

Step 1: Upload your PDF — PDF.js renders a preview of page 1
Step 2: Click and drag to select text or image regions you want to permanently remove
Step 3: Navigate to other pages using the page arrows and mark additional regions as needed
Step 4: Review the redaction list to confirm all selected areas are correct; click × to remove a mark if needed
Step 5: Click Apply Redactions — PDF-lib rewrites the content streams, removing text and image data
Step 6: Download the permanently redacted PDF

Who Uses This Tool

Law firms redacting attorney-client privileged information from documents produced in discovery
Healthcare providers removing patient names, diagnoses, and SSNs before sharing records for research
HR departments redacting personal salary information from shared compensation analysis documents
Financial institutions preparing loan documents for audit review with account numbers permanently removed
Government agencies processing FOIA requests where personal information must be withheld
Journalists protecting source identities in leaked documents before publication

Why Choose PDF AI Tools

We've built PDF AI Tools to replace expensive desktop software like Adobe Acrobat for 95% of common document workflows — at zero cost to you. Unlike competitors who gate features behind paywalls, add watermarks, or limit file sizes, our tools are genuinely free and genuinely unlimited. Your privacy matters: files processed client-side in your browser never touch our servers, and even AI-powered features use encrypted, auto-deleting processing pipelines.

Frequently Asked Questions

What is the difference between "redacted" and "blacked out" in PDF?

"Blacked out" means drawing a black rectangle on top of content — the content still exists in the PDF byte stream and can be recovered by copy-pasting or removing the black layer. "Redacted" means the content was permanently removed from the byte stream. Only permanent redaction is acceptable for legal, FOIA, and HIPAA compliance. This tool performs permanent redaction.

Will the metadata be cleaned too?

Yes. The metadata scrubbing step removes the Document Information Dictionary entries (Author, Creator, Producer, Keywords, Subject) and the XMP metadata stream. These fields frequently contain the original author's name, the software used to create the file, and other PII that would be embarrassing if discovered.

Does this work for scanned PDF documents?

For scanned PDFs (image-only pages), text redaction is not applicable — there are no text operators. Instead, use image redaction: the tool draws a white-then-black rectangle over the selected area on the page image, effectively blocking the scanned content. This is pixel-based redaction on the raster image.

Is this tool suitable for HIPAA or legal document redaction?

This tool produces permanently redacted PDFs suitable for most HIPAA and legal compliance purposes. For high-stakes submissions (court filings, government FOIA releases), we recommend having a qualified attorney or compliance officer verify the output, as no automated tool can guarantee 100% coverage of all disclosure risk.

Can I undo a redaction after downloading?

No. Permanent redactions cannot be undone — the byte stream content is gone. Always keep an unredacted original in a secure location before redacting. You can, however, undo individual region marks before clicking "Apply Redactions."