Black out what they shouldn't see, for real, before you send
You're about to send a document that has more on it than the signer should see: a full bank account number, another tenant's details on a reused form, your margin notes on page 4. Covering it with a black rectangle isn't enough, because the text is often still there underneath. Redaction in SignMaster removes it from the file before anyone gets a link.
Updated November 5, 2026 · 3 min read
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Why a black box isn't redaction
Most PDF editors and word processors draw shapes on top of the page. The words beneath stay in the file, and anyone can select them, copy them or run a search that finds them. Courts and agencies have published documents this way by accident. Real redaction deletes what's under the box and leaves nothing to recover.
| Tool | What it does | Use it for |
|---|---|---|
| Redact | Deletes everything under the box and prints a black bar in its place | Account numbers, ID numbers, anyone else's personal details |
| White-out | Covers the area with a white box; the content is still in the file | Tidying a stray mark or an old date you'll write over |
| Highlight | Marks text in yellow, green or pink, under the words | Drawing the signer's eye to a key clause |
Redact in the editor
- 1
Upload and open the draft
Redaction works on draft envelopes and templates, before sending. Upload the PDF, or scan the paper straight into the draft.
- 2
Choose Redact
In the Markup toolbar, pick Redact, then drag over each thing to remove. Draw every box you need across every page before applying.
- 3
Apply
Press Apply with the number of redactions. SignMaster warns that the content under the boxes is removed for good and that the whole document is rebuilt as flat page images. Confirm with Apply redactions.
- 4
Check, then send
Try selecting text anywhere in the document: there's none left to select. You can't send while any redaction box is still unapplied, so nothing slips through half done.
What changes when you apply
- Every page becomes an image. The document is rebuilt from sharp pictures of its pages with the black bars burned in, and SignMaster checks that the new file holds nothing but those pictures and no text at all.
- Text can't be searched or copied anywhere in it. That includes pages you didn't redact; it is the trade-off that guarantees nothing hidden in the original comes along. The file is bigger, too.
- It can't be undone. Keep your original file if you might need it.
- Signing works as normal. Place fields on any page the same as before. Redaction works on documents of up to 100 pages.
Redact before, never after
Do it before you send. Once a document is out for signature, its files can't change, and once it's signed, changing the PDF would break the fingerprint that proves it's the copy everyone signed. If a signed contract has to be shared later with something hidden, redact a copy for that purpose and keep the signed original untouched.
For a PDF you only need to share, not sign, the free redact PDF tool does the same job in your browser, with the file never leaving your device.
Questions? Answers.
Can someone recover text I redacted in SignMaster?
No. When you apply, the whole document is rebuilt from fresh page images with the bars burned in. Nothing from the original file is copied into the new one, so there is no text layer, hidden or otherwise, to recover.
Can I redact after sending?
No. Files can't change after an envelope is sent. Void it, duplicate it as a draft, redact the draft and send it again.
Is there a plan limit on redaction?
No. Redaction is part of the editor on every plan, including Free.
Why did the whole document turn into images?
That's how the hidden content is guaranteed gone. Rebuilding every page from a picture means nothing from the original file, on any page, can come along. Text can't be selected or searched afterwards, and the file is bigger.