What redaction actually has to do
A PDF page is not a picture. It is a list of drawing instructions: put this word in this font at this position, draw this image here, fill this rectangle black. When you "black out" a name by drawing a rectangle over it, you add one more instruction to the end of that list. The instruction that draws the name is still there. Anyone who selects the text, presses copy, searches the file or opens it in an editor gets the name back.
Proper redaction does three things. It removes the characters themselves, not just their appearance. It removes anything else that could carry the same information: the file's metadata, comments, bookmarks and attached files. And it leaves a visible mark so the reader knows something was removed.
How to redact a PDF with RedactKit
- Open the PDF. Drop it on the tool at the top of this page, or press Choose a PDF. It is read by your browser. Nothing is uploaded.
- Find what to remove. Type names, case numbers or anything else in Words to find, one per line. Each line matches any capitalisation and survives line breaks, so "Jane Example" still matches when "Jane" ends one line and "Example" starts the next. Then switch on the patterns you need: email addresses, phone numbers, UK National Insurance numbers, US Social Security numbers, IBANs, card numbers and dates.
- Review the matches. Every match is highlighted in yellow on the page and listed in the panel. Untick anything that should stay, such as your own organisation's switchboard number.
- Draw boxes for the rest. Signatures, photos, handwriting and scanned pages have no text to search. Drag across them to add a black box.
- Preview. Switch the viewer to Preview to see the pages exactly as they will be exported, with solid black bars.
- Export. Each page with a redaction is rebuilt as an image with the bars painted in, so the original words are not in the new file at all. Pages without redactions are copied across and keep their selectable text; their comments and links to other pages are removed so nothing can point back to a redacted page.
- Read the proof check. RedactKit opens the new file, reads every page back and tells you how much text is left on the redacted pages (it should be none) and whether any of the redacted items can still be found anywhere in the file.
Open your PDF in the tool above: it runs in this tab and the file never leaves your device. Documents up to 5 pages are free. Start redacting →
Why redacted pages become images
Removing individual characters from a PDF's drawing instructions is hard to get right. Fonts can be subset, text can be split into single letters, the same word can be drawn twice (once visibly, once invisibly for search), and form fields keep their own copy of what was typed. Rebuilding the page as an image avoids all of it: the new page holds one picture, made after the black bars were painted on. There is nothing underneath to recover.
The cost is that text on a redacted page can no longer be selected or searched, and the file gets a little larger. If you need the whole document flattened (for example, before publishing it), tick Rebuild every page as an image.
A checklist before you send a redacted PDF
- Search for every spelling: full name, first name, initials, nicknames, email handle.
- Look for indirect identifiers: job titles, addresses, dates of birth, staff and case numbers, vehicle registrations.
- Check headers, footers, tables and footnotes, which are easy to miss when skimming.
- Check the scanned pages by eye. No tool can search text in a picture without OCR, and RedactKit doesn't run OCR.
- Remove metadata. The author field often holds the name of the person who wrote the document. RedactKit does this on every export.
- Open the exported file, try to select text on a redacted page, and search it for a few of the redacted words.
What about Acrobat?
Adobe Acrobat can redact properly too, but its Redact tool is part of Acrobat Pro. On Adobe's UK pricing page (checked 8 November 2026) Acrobat Standard is listed without "Redact sensitive information", and Acrobat Pro costs £19.97 a month on an annual plan or £29.96 a month without one. If you redact a few documents a month, RedactKit's packs work out at 30p to 50p a document, and anything up to 5 pages is free.
Related: Black out text in a PDF · Remove personal information from a PDF · Remove metadata from a PDF