Why nothing uploads

The tools in the “Your files” aisle read the file you pick inside your own browser tab. The site has no endpoint that accepts files, so there is nowhere for one to go. You do not have to take our word for it.

What actually happens

• You choose a file. The page reads it into memory in your tab.
• The page’s own code works out the result and draws it on screen.
• When you close or reload the tab, it is gone. We do not save it anywhere.
• The pages are static files and tool pages use no third-party analytics.

How to check it yourself

1. Open the tool, then your browser’s developer tools (F12, or Cmd+Option+I on a Mac) and the Network tab.
2. Clear the list, then choose a file.
3. Nothing new should appear when you choose a file, and no request should carry your file. The page may still load its own small files (like the next page or script chunks) from this site; click a request and check that it has no body and goes to this site. If one carries your file, tell us.

The browser enforces it, not just us

Every tool page is served with a rule called a Content Security Policy that says its code may only talk to its own address (connect-src 'self'). A browser that follows the rule will block a request to anywhere else, even if a bug or a changed script tried to make one. You can see it in the response headers of the page in the Network tab.

What this does not cover

• The site is hosted on a normal web host, which sees ordinary page requests (like any website) but never your file.
• My host, Cloudflare, asks browsers to report failed page loads: the address and the error, never the contents of your file. Your browser sends those reports, not this page.
• Browser extensions you have installed can read pages. Use a private window with extensions off if that worries you.
• Anything you save or share from a tool, like an image of a card, is yours to share. Check it before you post it.
• Kits are files you download. They are not tools, and nothing in them runs on this site.