How is this different from drawing a black box?

Drawing a black rectangle only hides text visually — it can still be copied or extracted underneath. This tool deletes the matched characters from the PDF's content streams, so a copy-paste from the output reveals nothing.

Does the PDF leave my computer?

No. The file is read with the browser File API and rewritten using the native CompressionStream and DecompressionStream APIs. Nothing is uploaded, which is exactly what you want for sensitive documents.

Why did it say no matching text was found?

The PDF may be a scanned image with no real text layer, or it may use subset-encoded fonts that store glyph codes rather than literal characters. In those cases the text is not present as searchable strings and cannot be redacted this way.

Will the layout shift after redaction?

No. The matched characters are replaced with spaces of equal length inside the same text strings, so word positions and page layout stay intact while the sensitive content is gone.

Should I verify the result?

Always. Re-open the downloaded PDF and try to select and copy the area you redacted to confirm the text is truly gone before you share the document.

PDF Text Redactor — Gera Tools

Redacting a PDF properly means the sensitive text must be gone, not just hidden behind a black box that anyone can copy text out from underneath. This tool searches a text-based PDF for a phrase you specify and deletes those characters from the file’s content streams, all inside your browser so the document is never uploaded.

How it works

A text-based PDF stores its visible text as literal strings inside content streams, usually compressed with FlateDecode. The redactor works directly on those streams:

It parses the raw PDF bytes and locates each stream … endstream object.
For FlateDecode streams it inflates the data using the browser’s native DecompressionStream("deflate") — no external library is needed.
Inside the decoded text-showing operators (Tj and TJ), it finds your phrase within the parenthesized PDF strings and replaces each matched character with a space, so the glyphs vanish from the text layer.
It re-compresses the stream with CompressionStream, fixes the stream’s /Length, and reassembles a valid PDF for download.

Because the characters are removed rather than covered, selecting and copying the redacted region in the output yields nothing.

Notes and limits

This approach works on PDFs that contain a real text layer, which is the common case for documents exported from word processors and most digitally generated PDFs. It cannot redact text that is part of a scanned image — those pixels are not searchable text — and it cannot reliably touch PDFs that use heavily subset-encoded fonts storing glyph indices instead of readable characters; the tool tells you when no match was found. Spaces of equal length preserve the layout so nothing shifts. As with any redaction workflow, always re-open the downloaded file and try to copy the redacted area to confirm the sensitive text is truly gone before sharing. Everything runs locally in your browser.