Passive collection
What you sent ahead
You opened a page. Before you read a word of it, your browser had already answered a series of questions nobody asked it. Here are the answers, as this page received them.
Nothing below is stored, logged, or transmitted. There is no analytics script, no cookie, and no localStorage. Every value was computed in your own browser and disappears when you close the tab. Nothing loads from a third party either: the fonts are served from this site rather than from Google. Open the network panel while this page loads and you will see requests for this page's own files and nothing else. The one exception I cannot remove is GitHub, which serves the files and therefore sees your address. That, and why any of this exists, is in the ethics note.
Nothing was measured
Your content blocker stopped the script
If you are reading this, the panels that belong here never ran. The likely reason is
a content blocker: the script that fills this page is called fingerprint.js,
and blocking things by that name is exactly what those lists are for. uBlock Origin and
most privacy filters catch it.
Your blocker is not wrong. This page really does read your browser, and a tool that stops pages doing that without asking has done its job. The difference is only that this one shows you the results instead of keeping them, and it still sends nothing anywhere.
To see what your browser gives away, pause the blocker for this site and reload. To keep it on, nothing is lost: the rest of the site works, and the point of the page is arguably better made by your blocker than by my panels.
What is missing
One panel is deliberately absent. Your IP address reveals your city and your internet provider, and it arrives before any of the above, in the connection itself. Reading it needs a server, and this site is static files on GitHub Pages, so it has no server to read it with. It is the single most identifying thing you sent, and the only reason it is not on this page is that the hosting cannot reach it.
That is worth sitting with. The most revealing signal here was withheld by an accident of hosting rather than by anyone's restraint.