About SladdPDF: browser-local PDF redaction

SladdPDF is a free tool for redacting PDF documents that runs entirely inside your web browser. Your file is opened, edited and saved on your own device — it is never uploaded to a server, ours or anyone else's. This page explains what the tool does, how the technology works, who it is built for, and exactly where its limits are.

What is SladdPDF?

SladdPDF is a free, browser-based tool for redacting PDF files — permanently removing names, identity numbers, account details or whole paragraphs before a document is shared. There is no account, no registration and nothing to install: you open the page, drop in a PDF, draw boxes over what has to go, and export a clean copy.

The name comes from sladding, the Norwegian word for redaction, and the site is published in Norwegian and English.

What problem does it solve?

Most free PDF tools on the web solve the redaction problem by asking you to upload your document to a server you know nothing about. For a holiday itinerary that is a fair trade. For a witness statement, a payslip or a case file, it means handing the most sensitive document you own to an unknown party under terms you almost certainly did not read — and once that copy leaves your device, you can no longer verify how long it is kept, who can open it, or which country it comes to rest in.

There is a second, quieter problem: plenty of tools call it redaction when they simply draw a black rectangle on the page. The text survives underneath, and anyone can select, copy and paste it back out. SladdPDF answers both problems at once — nothing is uploaded, and the recommended export mode destroys the hidden content instead of covering it. The full reasoning is in why local processing is safer than uploading.

How does the technology work?

Everything runs in your browser. SladdPDF uses pdf.js to render the pages you see on screen and pdf-lib to write the redacted file, both as JavaScript inside your own tab. When you choose a file it is read from disk into the tab's memory, edited there, and written back to your downloads folder. No network request carries the document. A useful side effect: once the page has loaded, the tool keeps working with the network switched off — you can disconnect entirely, redact a document and download the result. That is the simplest proof there is that the processing is local.

On export you choose between two modes. Secure mode rasterizes every page to a flat image after the redactions are applied, so the text, layers and hidden objects beneath a redaction box are destroyed and cannot be recovered. Fast mode draws vector overlays instead — quicker and smaller, but the tool warns you that underlying text may in some cases still be extractable. For anything genuinely sensitive, use Secure mode.

The export step can also strip the document's metadata: title, author, the creating software and other hidden tags that quietly travel with a PDF. Image quality (DPI) and compression are adjustable. The rest is ordinary editor comfort — undo with Ctrl+Z, page thumbnails, zoom — in any modern browser on Windows, macOS, Linux and ChromeOS.

Who is SladdPDF for?

SladdPDF is for anyone who has to hand over a document containing information the recipient should not see. In practice that covers a lot of desks:

• Lawyers preparing disclosure, where privileged material and third-party details must come out before the file goes across.
• HR and people teams handling personnel cases, references and sick notes that go to one party but not another.
• Public-sector case handlers answering access-to-information requests, who must remove exempt information before a file is released.
• Journalists publishing obtained documents, where one un-redacted line can identify a source.
• Individuals sending a bank statement to a landlord, a payslip to a lender or a CV to a recruiter.

What those cases share is a document you would rather not upload to an unfamiliar website — which is the whole reason the tool works the way it does. If you are new to it, the step-by-step guide to redacting a PDF walks through a first document.

What SladdPDF stands for

Two principles shape the product. Privacy by design means the safest way to protect a document is never to send it anywhere. We do not promise to delete your files after two hours or to guard them in a data center, because there is no file of yours to delete or store. That guarantee is structural rather than contractual — the only kind you can verify yourself.

Honesty about limits means saying the awkward parts out loud, before you have done the work rather than after.

The same honesty applies to this website. sladdpdf.com uses Vercel Web Analytics to count page views — aggregate numbers for which pages are read and how many visits they get, with no cookies, no personal profiles and no cross-site tracking. That is about pages, not documents: your PDF is never part of any measurement because it never leaves your device. The site sets no cookies at all, but we do still count page views — a content blocker stops that too, and the tool works fine without it. The precise claim we make remains "your files are never uploaded" — the privacy page has the detail.

And SladdPDF is not always the right tool. If you redact 300-page bundles weekly, or need an organization-wide workflow with audit trails, desktop software such as Adobe Acrobat Pro fits better. We would rather say so than sell you a workaround.

Contact

Questions, bug reports or suggestions? Email issaafakattan@gmail.com. Since the tool has no user accounts and never receives your files, email is the one channel there is — and it is read.