Read any page like
you built it.

DevTools answers one element and one question at a time. This reads the whole page at once and hands back a ranked list - every element that overflows the viewport, every stacking context, every image shipped at twice the size it renders, a heatmap of which rule actually won. It also answers questions DevTools never asks: what the page was built with and how each detection was made, what its design tokens are, and how much of the markup reads as generated. It floats over the page rather than docking beside it, so what you are inspecting keeps the width it had.

A hostname, integer counts, class-name strings, and the page title plus heading text after truncation and redaction. No body text, no input values, no full URL. The privacy page lists every field.

activeTab and scripting, granted for the tab you are on when you click. That is what lets it read the page you asked about. It does not request access to all sites, and neither built manifest contains a host permission.

Yes. It reads whichever tab you are on when you click, which includes localhost, a staging host and anything you are signed in to. There is no list of sites it works on because there is no list of sites at all.

For naming the stack of the page in front of you, yes: every detection keeps the marker that matched beside it, and nothing asks you to sign in. For prospect lists filtered by what thousands of sites run, no - that is what Wappalyzer sells, and the comparison page, LoupeKit vs Wappalyzer, says where each is the better answer.

For 24 hours from install every tool is open, with no card and no account. After that the panel locks until this browser has Pro - monthly, or one Lifetime payment. Settings stays reachable, and so does the field a licence key goes into, but nothing reads a page while it is locked. The panel counts the trial down where you can see it, so the lock is never a surprise. Audits are not counted during the trial. Readings fetched from our server and what we keep for your account - baselines, settings backups and evidence packs at a link - begin with the plan.

One payment, no renewal, and it carries exactly what the monthly plan carries. That is a constraint in the code rather than a promise in the copy: both plans are held to one shared feature list, so neither can quietly grow a perk the other lacks. The prices on this site are the prices Stripe charges; if you ever find the two disagreeing, the checkout page is the one that is right and the other is a bug we want reported.