How it works

Privacy by design

"Your files never leave your device" is an architectural claim, not a promise, and architecture is verifiable. Here's exactly how, and how you can check it yourself.

How the tools actually run

Every tool on this site is a small piece of JavaScript (built from @officeutils/core) that ships to your browser along with the page. When you drop in a file, that code reads its bytes directly in memory and runs entirely inside a Web Worker on your device. It never constructs a request to send that file anywhere. There is no upload endpoint for these tools to call, because we didn't build one.

Verify it yourself

  1. Open any tool page and open your browser's DevTools (F12 or Ctrl+Shift+I).
  2. Switch to the Network tab and clear it.
  3. Add a file and run the tool.
  4. Watch the Network tab. It stays empty for the whole job. No request appears.

We run this exact check automatically, for every tool, before any change ships (our "no-network" test).

What does leave your device

Nothing about your files does. Separately, we use Cloudflare's cookieless web analytics for aggregate page-view counts, and a small set of anonymous product events (which tool ran, whether a paywall was shown). We never log a file name, a file's contents, or anything that could identify what you processed.

Offline and installable

Because processing never depends on a server, OfficeUtils keeps working once the page has loaded, even with no connection, and it can be installed as an app on desktop or mobile.