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CMS Detector

Enter any website address and find out what it is built with, along with the exact signals behind each result.

About this tool

This tool loads the page once and looks for known fingerprints: the generator meta tag, asset paths and JavaScript globals in the HTML, response headers, and cookie names. Evidence is weighted rather than matched one by one, so a real site can be reported as several things at once, for example a framework, a content source, and a host. Every result lists the signals that produced it, so you can judge it for yourself.

People usually reach for a tool like this for one of a few reasons: sizing up what needs to be replicated before a redesign or migration, checking what platform a well-ranking competitor built on, or just plain curiosity about a site you're looking at. The two best-known tools in this space, BuiltWith and Wappalyzer, are excellent and far broader in scope, they track well over a thousand technologies across categories like analytics, payments, and marketing tools, not just the CMS. Wappalyzer's free tier caps out at 50 lookups a month before it asks for a paid plan, and BuiltWith's full historical data sits behind a paid subscription. This tool is narrower by design (platforms, frameworks, and hosting, not the full technology graph) and free with no lookup limit, and every result shows you the exact signals behind it rather than a single opaque match.

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Frequently asked questions

The tool fetches the page once and scores known fingerprints: the generator meta tag, script and stylesheet paths, JavaScript globals, HTTP response headers, and cookie names. Each signal carries a weight, and platforms that gather enough weight are reported with a confidence level and the list of signals that matched.
Because most modern sites genuinely are several things at once. A store might be Shopify for commerce with a separate frontend framework, and a blog might be Next.js for the frontend with a headless CMS behind it and a separate host. Forcing a single label would be wrong more often than it is right, so results are grouped by role instead.
They describe how much independent evidence was found. Low means a single signal matched, which is worth knowing but easy to get wrong. Medium means two independent signals agreed. High means several did, including strong ones that are hard to fake. Confidence is deliberately shown as a band rather than a percentage, because detection is inference from observable evidence and a precise-looking number would overstate how exact it is.
Some setups hide almost everything: headless builds where the CMS never appears in the delivered page, security plugins that strip the generator tag and identifying headers, aggressive CDN caching, or sites that block automated requests outright. When the evidence is not there, the tool reports nothing rather than guessing.
No. The address is used to fetch the page for that one request and is not saved. Only public web addresses can be checked: requests to private or internal network addresses are refused.
A few common, practical reasons: checking what you'll need to replicate before redesigning or migrating your own site off its current platform, seeing what a competitor who ranks well happens to be built on as part of researching their setup, or vetting a platform choice before committing to it yourself by seeing what similar sites in your space actually use. It's also just genuinely useful for spotting whether a site is a fully custom build or running on a familiar platform underneath.
BuiltWith and Wappalyzer are the established tools in this space and cover a lot more ground, well over a thousand technologies across analytics, payments, marketing tools, and more, not just the CMS or framework. Wappalyzer's free tier is limited to 50 lookups a month, and BuiltWith's deeper historical data sits behind a paid subscription. This tool is intentionally narrower, focused on CMS, page builder, framework, and hosting detection, and it's free with no lookup cap, with every result showing the specific signals that produced it rather than a single unexplained match.
No, it identifies platforms and major add-ons at the level of "this site runs WordPress with WooCommerce," not individual theme names or a full plugin inventory. Detecting a specific theme or every installed plugin would require deeper inspection than a single page fetch, and isn't part of what this tool does.

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