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See what any website is built with.

Detect the CMS, framework, hosting, analytics, and libraries behind any URL.

Questions

How does the detector figure out what a site uses?
It fetches the page and reads the public signals every site exposes: HTTP headers, meta generator tags, cookie names, script and asset paths, and known file patterns. Nothing intrusive — the same evidence a browser already receives.
Why does it miss some technologies?
Server-side languages, databases, and anything behind a CDN or reverse proxy often leave no public fingerprint. Sites can also strip headers and generator tags deliberately. Treat empty results as unknown rather than absent.
Is it legal to check a competitor's tech stack?
Yes. The tool only reads what a site publicly serves to any visitor, which is the same information available from your browser's developer tools. It is a standard part of competitive and technical research.