How our browser tools work
When you use one of our file tools, such as resizing a photo or merging two PDFs, the work happens inside your web browser, on your own phone or computer. Your files are never uploaded to us or to anyone else.
What happens when you add a file
- Your browser reads the file from your device into its own memory.
- The tool's code, which your browser downloaded with the page, does the work right there: decoding, resizing, merging, converting.
- The result is made in your browser too. When you press Download, your browser saves it straight to your device.
The heavy work runs in a separate part of your browser under a strict security rule set by our site: it can load only our own code and can't contact any other website. The rest of the page can reach only our own site and Google Analytics, and our code never sends your files to either.
The resume checker keeps your resume just as close: it reads it inside its own separate frame, on check.modernnicheworld.com, which can't contact any other website at all, and the page around that frame can't see inside it.
It keeps working offline
Once a tool has loaded and run once, you can switch off Wi-Fi and keep using it on that open page. That's a simple way to see for yourself that nothing needs the internet.
How to check it yourself
On a computer, open your browser's developer tools (F12 in most browsers), choose the Network tab, then use a tool. You'll see the tool's own code load, but no request carrying your file.
On a phone, use the offline check above instead.
What the page itself sends
Like the rest of this site, a tool page counts visits with Google Analytics, as the privacy policy explains. That records the page you visited, never your files, their names or their contents. On the resume checker, if you accept cookies, it also counts steps such as a check being run, again without any of your resume's content.
Limits
Because the work happens on your device, very large files depend on how much memory your device has. Each tool shows its size limit, and phones may run out of memory sooner than computers.