Privacy and security: how SladdPDF handles your files

SladdPDF redacts PDF files entirely inside your browser. Your document is opened, edited and saved on your own device, and no copy of it is ever sent to a server — not ours, not anyone's. This page explains in plain language what that means, what the website itself does collect, and how you can check every claim on this page for yourself.

What happens to your PDF file?

Nothing leaves your device. When you open a PDF in SladdPDF, your browser reads the file from your disk into the memory of the tab you have open. The redaction is then done by JavaScript and WebAssembly running in that same tab — pdf.js to display the pages, pdf-lib to write the finished document. When you export, the new PDF is saved straight back to your own disk by your browser.

The same goes for everything you do in the tool: the boxes you draw, the metadata you strip, the image quality you pick. There is no upload step, because there is no server-side component that touches your document.

How can you check this yourself?

You do not have to take our word for it, and there are two tests that take about a minute each.

The first is your browser's Network tab. Open developer tools (F12 in most browsers), switch to Network, then load a PDF and redact it. You will see the page's own files and a small analytics request to the site's own /_vercel/insights endpoint — but no request carrying your document. An upload is hard to miss: it shows up as an outgoing request roughly the size of your PDF.

The second test is stronger and needs no technical knowledge at all. Load the page, then disconnect: turn off Wi-Fi, switch on airplane mode, or unplug the cable. Now redact your PDF as normal. Everything still works, because everything needed was already on your machine. A tool that quietly uploaded your file could not possibly finish the job with the network switched off.

Does SladdPDF work offline?

Yes. Once the page has loaded, SladdPDF keeps working without an internet connection. The code that performs the redaction is already in your browser by then, so nothing more needs to be fetched. That is a direct consequence of doing the work locally — and it is why the offline test above proves so much.

What is stored in your browser?

Your Pro licence key is stored locally in your browser. The free version has no page limit; if you buy Pro for high-resolution 300 DPI export, the key you enter is saved in your browser's localStorage on that device so you do not have to retype it. You can see it yourself in developer tools under Application → Local Storage.

Clearing your browser data removes the key, and you will then need to enter it again. It is not attached to a profile and does not travel to your other devices on its own, because there are no accounts to attach it to.

What does the website itself collect?

The website uses Vercel Web Analytics for aggregate visit statistics. Pages on sladdpdf.com load a small script that counts page views: which pages were opened, how many times, and roughly which country the visit came from. It is cookieless — it sets no cookies at all, builds no personal profiles, does no cross-site tracking and is never used for advertising. We still count page views, and we say so plainly, because the honest claim is not “we collect nothing” — it is “your files are never uploaded”.

The distinction matters. Analytics covers your visit to the website, not the contents of your documents — and it could not cover them: your PDF never leaves the browser tab, so there is no route by which it could reach an analytics service.

If you would rather not be counted, you can stop it. Browser privacy settings, built-in tracking protection, or an ad or content blocker will all prevent the analytics script from loading. The redaction tool is unaffected — you already know that, because it keeps working with the network switched off entirely.

Do you need an account?

No. SladdPDF has no user accounts, no registration and no password to store. You open the page and start working, and there is no user database with your name in it.

Everything at a glance

Nothing you put into SladdPDF leaves your device — only the fact that you visited the website does.

This page is a plain-language explanation of how the tool works, not a formal legal document. If any of it sounds too good to be true, settle it the quick way: load the page, disconnect, and redact something.

Privacy contact

If you have questions about privacy on sladdpdf.com, or want to raise a concern, contact issaafakattan@gmail.com. Users in the EU/EEA also have the right to complain to their national data protection authority (in Norway, Datatilsynet).