Redact a PDF — properly
Most "redacted" PDFs still contain the text under the black boxes. Here's how to remove it for real — and prove it's gone.
RedactWorks finds the sensitive data in your PDF, highlights every item for your approval, removes the approved text permanently — then re-scans the finished file and refuses to release it if anything you approved is still there. 3 free documents, no card required.
Works with PDF, Word, Excel, PowerPoint, scans (OCR) and email files. Each free redaction covers a whole document, up to 50 pages.
Or try it right here — no signup, no upload
The AI has already scanned this sample. Every free redaction tool makes you the detector — you draw the boxes and hope you didn't miss one. Here, the finding is done for you; your job is the decision. Click any highlight to keep it visible, then approve.
Student Jordan A. Pemberton (ID 4415-882) met with the counselor on March 14 regarding a schedule change. Guardian Maria Pemberton was reached at (555) 014-2291.
Records request verified against SSN 123-45-6789. A follow-up note was sent to m.pemberton@example.com. No further action required.
The AI found 6 items — the decision is yours. Click any highlight to keep it visible; nothing is redacted until you approve.
Verified. 6 items permanently removed — the text is deleted, not covered — hidden data stripped, and the finished file re-scanned to prove it. Kept visible: none.
Now try your own — 3 free, no cardSynthetic sample — every name and number is invented. The AI can highlight, but it can't redact: only your approval applies a black box.
Why the black-box method leaks
A rectangle drawn over text — in a PDF viewer, or by printing a marked-up page back to PDF — only covers the words. The characters remain in the file's text layer, one select-and-paste away. Nearly every famous redaction leak worked exactly this way. And the page isn't the only carrier: PDF metadata, annotations, form fields and embedded content survive page-level edits entirely.
What proper PDF redaction does
Three things, all of them checkable: the approved text is removed from the file (not hidden behind a box), the document's hidden data is stripped (metadata, annotations, form fields, embedded content), and the finished file is re-scanned to verify the approved items are actually gone. That last step is the one almost every tool skips — a claim of permanence isn't the same as a check of the output.
How it works in RedactWorks
- Upload your PDF. Detection runs automatically — names, SSNs, account numbers, addresses, medical details, dates of birth and more.
- Review the highlights. Every finding is a checkbox over still-visible text. Uncheck what should stay; add anything missed. High-risk categories (SSNs, financial and medical data) stay locked on. Nothing is removed until you approve.
- Approve — and let the verify pass check the output. The text under every black box is permanently removed and hidden data is stripped. Then the file is re-extracted and re-scanned: if any approved item survives, your download is blocked.
No card required. Your documents are never used to train AI — enforced by Google Cloud's Vertex AI Training Restriction.
Common questions
Is drawing a black box over text real redaction?
No. The box only covers the text; the characters stay in the file and can be revealed with select-and-paste. Real redaction removes the text itself and strips the document's hidden data.
How do I know the redaction actually worked?
Check the output, not the process: try to select and copy over the black boxes, and inspect the metadata. RedactWorks automates this — the finished file is re-extracted and re-scanned, and delivery is blocked if anything you approved is still present.
Can I redact a PDF for free?
Yes — every new account includes 3 free redactions, no card required. Each covers one whole document, up to 50 pages. After that: a 3-redaction pack for $1.99, or $14.99/month for 150 a month.
What about scanned PDFs?
Scans are read with OCR and go through the same detect → review → verify flow. If a file is genuinely unreadable, RedactWorks says so instead of reporting a clean result it can't stand behind.
Want the deep dive?
The full guide — including how to redact properly in Adobe Acrobat and macOS Preview, and a pre-release checklist — is on the blog: How to redact a PDF (and verify it actually worked). For the security angle, read what "secure document redaction" really requires.