AI website detector tools compared: checkers, extensions and browsers

An AI website detector tells you whether a site was likely built with an AI app builder such as Lovable, Bolt or v0. The category is new. By late 2026 there are many of them, in four shapes: web checkers, browser extensions, tech-stack profilers and, in our case, a whole browser. This guide compares the shapes rather than ranking individual products, because the shape decides most of what a tool can and can't do.

We make Kitsuvo, which is one of the options below, so weigh our view with that in mind. We have tried to be fair about where each approach is the better choice.

Web checkers: paste a link, get a verdict

A web checker is a site where you paste an address. Its server fetches the page, looks for builder fingerprints, and returns a verdict or a percentage. The better ones show the evidence they matched, render JavaScript-heavy pages in a real browser, and check DNS records and response headers too.

• Good at: one-off checks, no install, and sharing a result with someone else. Some offer an API for checking many sites.
• Weak at: anything you have to remember to do. You will check the one site you were already suspicious of, not the ten you opened without thinking.
• Privacy: the checker learns every address you paste. That is fine for public sites and worth thinking about for anything else.

For a side-by-side of two named checkers, AI Website Detector and Is That Vibe Coded, see AI website detector alternatives, and for seven named tools in one list, the roundup of best AI-generated website detectors.

Browser extensions: a badge in the toolbar

Extensions run inside Chrome, Edge or Firefox and score the page in the current tab. Most of the ones we found in this niche are small and recent.

• Good at: staying in the browser you already use, and checking passively as you browse.
• Weak at: seeing everything. Extensions read the page the browser hands them; response headers and the full list of loaded scripts are harder to get at, and some extensions only check the domain. Few can hide a page before it shows, and few touch search results.
• Privacy: a detector extension needs permission to read every site you visit. Check whether it sends pages to a server and what its owner does with them. Small extensions can change owners, so check who publishes one before you rely on it.

Want to try the Kitsuvo extension in your own browser? Its free developer preview has manual-install packages for Chromium and Firefox; public store listings are not available yet. See the browser packages and installation steps.

Tech-stack profilers: what is this built on?

Wappalyzer and BuiltWith identify website technologies for sales and research teams; Wappalyzer says it was founded in 2008 and BuiltWith in 2007. As read on October 10, 2026, Wappalyzer's public directory has entries for AI builders including Lovable, Base44, Emergent and Durable, each with a count of the websites it tracks. BuiltWith has a Lovable page in its trends section; its technology pages showed a verification check when we tried to load them, so we have not confirmed which other AI builders it lists. We did not find Bolt or v0 in Wappalyzer's directory.

• Good at: breadth and maturity. Wappalyzer's directory lists 8,166 technologies and BuiltWith's home page cites 127k+, on their own pages as read on October 10, 2026.
• Weak at: judgement. They tell you a site uses React, Tailwind and Lovable. What they publish describes technology lookups and lead lists, and we found no verdict, evidence weighting or impersonation warning in it. That fits the sales and research market they describe.
• Privacy: a lookup site sees the address you enter, and an extension may send the sites you visit to its maker's servers, so read its privacy policy first.

A detector browser: every page, as it loads

This is the approach we took with Kitsuvo, our no-AI web browser. Instead of adding a detector to a browser, the browser is the detector. Every page is scored from 0 to 100 as it loads, with the builder's name in the address bar and the evidence a click away.

• Good at: coverage without effort, since it sees everything a page loads, including scripts and response headers. It can mark and hide likely AI-built results on search pages, hide likely AI-built pages behind a notice, and warn about look-alike sites asking for a password.
• Weak at: asking you to switch browsers, which is a real cost. And it only judges pages you open; for checking a list of sites in bulk, an API checker is the better tool.
• Privacy: detection runs on your computer and Kitsuvo has no telemetry. Optional AI second opinions send a short page digest straight to the AI provider you choose, never to us.

What to look for in any AI website detector

1. It shows its evidence. A bare "87% AI" with no reasons can't be checked. Look for tools that list the exact script, header or domain they matched.
2. It names the builder only on a fingerprint. Style alone can't tell Lovable from Bolt from a human using the same components. A tool that names a builder from a gradient is guessing. The fingerprints themselves are listed in how to tell if a website was built with an AI builder.
3. It admits doubt. "No strong AI signs" is more honest than "100% human". Sites can be stripped of every trace.
4. It doesn't treat AI-built as dangerous. Built with AI is context. Impersonation is danger. Good tools keep them apart.
5. It is clear about data. You should know, in one sentence, what leaves your computer and where it goes.

A note on AI text detectors

Tools that guess whether text was written by AI are a different category, and a shaky one for this job. They are known to misfire on short and formulaic text, and on writing by non-native English speakers. Website detectors work better because they rely on how a site was built, which leaves hard evidence, rather than on how it reads. The evidence on their accuracy is in are AI content detectors accurate? For what the wording can still tell you, see the phrases that give away AI-written website copy.