How to Redact Sensitive Information from a PDF

Why Most PDF Redaction Fails

The most common "redaction" mistake: drawing a black rectangle on top of text in Acrobat or Word, then saving as PDF. The text is still there — it's just hidden behind a black box. Anyone who opens the file in a text editor can read every word.

True redaction permanently removes the underlying data from the PDF file structure.

What SynthPDF Redaction Does

Our redaction tool:

1. Lets you select rectangular areas on each page (click and drag)
2. Removes the text content and image data from those areas at the PDF level
3. Replaces them with solid black fills — permanently, with no recoverable data underneath

Common Redaction Use Cases

• Legal documents: Remove client names, SSNs, dates of birth before sharing drafts
• Financial records: Black out account numbers, routing numbers, signatures
• Medical records: Remove patient identifiers (HIPAA compliance)
• HR documents: Hide salary information before sharing job descriptions
• Court filings: Redact protected information per court rules

Step-by-Step Guide

1. Upload your PDF to the Redact tool below
2. Navigate to each page that contains sensitive information
3. Click and drag to draw a redaction area over the text or image to remove
4. Add as many areas as needed across all pages
5. Click Apply Redactions — the content is permanently removed
6. Download your redacted PDF

Verification

After downloading, open the redacted PDF and try to copy-paste the text in the redacted areas. You should get nothing — confirming the data is truly gone, not just hidden.