Website technology checker

Use this website technology checker to identify software from visible markers and DNS. Inspect disclosed versions and evidence, then compare two sites with AI crawler access notes.

Free, no account. Ten checks per hour across the AI readability, mobile and technology checkers. Comparing two sites uses two checks.

Checks public HTML, headers, cookie names, asset URLs, DNS, robots.txt and llms.txt. No JavaScript is run. Results can be cached for five minutes.

A website technology checker identifies software from public headers, cookie names, generator tags, assets and markup. This checker adds mail and CDN evidence from DNS, disclosed versions and comparison between two sites. AI access notes report robots.txt rules and llms.txt presence. Every detection shows its evidence. Missing markers do not prove software is absent.

How to use this checker

Check one site or compare two
Enter public URLs. Each site uses one of the ten shared hourly checks and has its own result, so one failure does not hide the other. Successful responses can be cached for five minutes.
Inspect the evidence
Our identified checker respects applicable robots.txt rules and reads up to 3 MB of HTML without running JavaScript. Original signatures inspect headers, cookie names, generator tags, asset URLs and markup. Versions appear only when an explicit version marker is visible. Cookie values are never returned.
Read DNS and AI access separately
Bounded MX lookups identify a domain’s mail provider; CNAME records and published Cloudflare IP ranges can identify hosting or a CDN. Source links accompany DNS evidence. AI bot rules come from robots.txt. llms.txt is checked for a readable Markdown response, then linked to the full validator.

Questions about this checker

They are evidence matches, not a complete inventory. A proxy can hide the origin server, public files can be copied, and software can remove its markers. Versions are only the numbers explicitly disclosed in headers, generator tags or recognizable asset paths. No generic cache query parameter is treated as a product version.

No. Builders such as Squarespace and Webflow have crawler settings, but detection does not show whether those settings are enabled. This report checks actual robots.txt rules for four AI bots at the requested URL. A firewall may still deny a real crawler even when robots.txt allows it. Use the AI readability tool to test response delivery.

The endpoint returned a readable non-HTML response with a Markdown heading. Presence does not validate its links or content, and does not guarantee use by an assistant. Open the linked llms.txt validator for structure and optional link checks.

Only public pages are checked. No browser session, login cookie or JavaScript execution is used. Robots denial stops the page request. Refusals, challenges, truncated responses and incomplete DNS lookups keep their limitations visible.

Related tools

  • Can AI read my website

    Can AI read my website? Compare raw HTML text, headings, links and structured data across crawler requests. Check access rules and spot JavaScript shells.

  • Page speed checker

    Run a page speed test for mobile and desktop with Google Lighthouse. Review Core Web Vitals when available, compare a competitor and choose a fix.

  • SEO checker

    Use this SEO checker to audit up to 25 pages for crawl and on-page issues. Review affected URLs and a fix list, or add a small competitor sample.

Check your business in AI answers

A page that crawlers can read is the starting point. The free AI visibility scan shows how assistants answer about your business and what to work on next.

Run the free AI visibility scan