What you get free
RedactKit's free tier is the whole product for short documents. If your PDF has 5 pages or fewer you can search, draw, preview and export as many times as you like. The output is a properly redacted PDF: redacted pages rebuilt as images, the rest copied across, metadata stripped. There is no watermark, no daily limit and no email address to give.
Most letters, forms, statements, contracts and invoices fit in 5 pages. For longer documents, such as case bundles, board packs and subject access request responses, one credit covers one document of any length. Credits come in packs: 10 for £5 or 50 for £15. They never expire, and exporting the same file again after a fix doesn't use another credit.
Try it on the sample file or your own PDF: it runs in this tab and the file never leaves your device. Documents up to 5 pages are free. Start redacting →
Why "free" redaction tools differ so much
Three questions separate a good free redaction tool from one that only looks like it worked.
- Is the text really removed? A tool that draws a black rectangle on top of the text leaves the words in the file. Test any tool by redacting a word, opening the result and trying to select or search for it.
- Where does the file go? Most online PDF tools upload your file to their servers to process it, and delete it later. That is often fine, but it is the wrong default for the documents people redact: HR files, medical letters, court papers, bank statements.
- What's left besides the page? The author, the software used, revision history and attached files can identify people as easily as the text can.
How the common options compare
Facts below are from each vendor's own page, checked on 8 November 2026. Prices and limits change, so check before you rely on them.
| Tool | Cost to redact | Where the file is processed |
|---|---|---|
| RedactKit | Free up to 5 pages; then £5 for 10 documents or £15 for 50 | In your browser. Not uploaded. |
| PDF24 Tools (online) | Free, funded by advertising | On PDF24's servers; files deleted after one hour (its redact page says so). Affected pages are rasterised on saving. |
| Smallpdf | Free with usage limits; Pro for unlimited redactions | Its page says processing happens on secure servers and files are deleted after one hour. |
| Sejda | Free with page and hourly limits; Web Week Pass £5 for 7 days; Desktop+Web £63 a year | Online (Sejda also sells a desktop app). |
| Adobe Acrobat Pro | £19.97 a month on an annual plan (UK); redaction isn't in Acrobat Standard | Desktop app on your computer. |
If you redact many long documents every week, a desktop app or a subscription may suit you better. If you redact the occasional document and would rather it never left your laptop, RedactKit is built for that.
Is browser-based redaction safe?
RedactKit is a web page that runs its PDF code inside your browser tab: pdf.js (the PDF engine in Firefox) to read and draw pages, and pdf-lib to write the new file. Your PDF is read from your disk into the tab's memory and the redacted copy is saved back to your disk. You can check this yourself: open your browser's developer tools, watch the Network panel while you export, and you will see no upload. The only thing the page sends is a credit check for documents over 5 pages, which sends your key and a fingerprint (a SHA-256 hash) of the file so a second export of the same file is free. A hash cannot be turned back into the document.
Free tier limits, plainly
- 5 pages or fewer: free, unlimited.
- 6 pages or more: one credit per document, any length.
- No OCR: scanned pages can be redacted with drawn boxes, but search can't find words in them.
- Password-protected PDFs open if you know the password; every page is then rebuilt as an image.
Related: How to redact a PDF · Black out text in a PDF