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How it works
Your file stays on this computer. There is no upload button here, because there is nowhere to send it. Each tool runs inside the page you open — like a calculator on a page, it keeps working once it has loaded.
Files this matters for
A payroll export. A signed contract. A medical form. A spreadsheet of customer email addresses. Anyone who opens one of those can read every name, every address, every amount. That is the kind of file this page is about.
What happens when you choose a file
You choose a file from your own folders, the same way you’d open it in Excel. Your browser opens it and keeps it on this computer. The tool works on it here, then hands you the result as a download.
Your file is never sent, so there is nothing for anyone to keep.
Check it yourself, in about thirty seconds
If you’d rather check for yourself, here’s the quickest way.
- Use any tool on this site once, on any sample file, with the settings you want.
- Turn off your wi-fi.
- Do the same thing again in this same tab, without reloading.
It still works. Everything the tool needs is already on this computer by then.
What does load from this site
The page itself, and the code for whichever tool you open — some of it when you first run the tool, which is why the check above starts with using it once. That is what happens when you open any web page. Nothing goes the other way. The file you open here is read by your browser and never sent.
If you know what a Content-Security-Policy is
The site is a set of static files with no application server, no database and no upload
endpoint. Every page here is served with a Content-Security-Policy that
includes connect-src 'none'. Your browser enforces that rule on us, not the
other way round. This page cannot open a fetch, XHR, WebSocket or beacon connection to
any address.
The same policy carries form-action 'none', so the page cannot submit a
form either. This covers connections the page opens, not links you follow or files you
download.
To watch this happen: press F12, open the Network tab, and use any tool here. The page and that tool’s code arrive. Your file does not go out. The header itself is on the document request, under Response Headers.
A site that uploads your files could not send that header without breaking itself.
Why there are no limits here
The work happens on your computer, so there is nothing here to ration. No daily limits, no queue, no watermark on your file and no account to create. The only size limit is how much your own computer can hold at once.
What these tools can’t do
Some jobs are out of reach here. These tools can’t read the text out of a scanned page, so a scanned PDF stays a picture. Software that does that on your own computer, such as Adobe Acrobat, will read it.
What this site records
Nothing about your files, because they never leave your computer. We look at page-view counts by country, from the records the host keeps in order to serve the page. Nothing is linked to a person. The privacy page has the full detail.