Free CMS Detector

Every platform leaves fingerprints in the pages it serves: a generator meta tag, a platform-specific response header, a CDN hostname, a predictable asset path. Enter a domain and this checker fetches the site's homepage, reads its HTML and HTTP response headers, and matches them against signatures for 17 platforms. It shows the evidence behind every match rather than just asserting an answer, so you can judge it yourself.

What it looks for. Strong signals are ones a site rarely produces by accident: a generator meta tag naming WordPress, Squarespace, Webflow, Ghost, Drupal, Joomla, Astro or Framer; platform response headers such as Shopify's x-shopify-stage, Wix's X-Wix headers or Drupal's X-Generator; platform asset hosts such as cdn.shopify.com, static.parastorage.com (Wix), static1.squarespace.com, website-files.com (Webflow) and the BigCommerce CDN; a reference to the WordPress REST API; and framework build output such as /_next/static/ for Next.js, __NUXT__ for Nuxt or ___gatsby for Gatsby. Weak signals are suggestive but easy to copy: wp-content and wp-includes asset paths, Webflow page attributes, Astro island markers, WooCommerce body classes, Shopify theme globals and the Framer asset host.

How confidence is scored. Each strong signal is worth 2 points and each weak one 1 point. Three or more points is high confidence, exactly 2 is medium, and 1 is low, so a single strong signal on its own reads as medium. The platform with the most points becomes the main result; every other platform with evidence is listed under Other signals, because sites genuinely run on more than one layer, such as WooCommerce on WordPress or a storefront on a JavaScript framework. If the homepage has no strong signal at all, the checker also fetches /blog (or /news when there is no blog) and marks anything it finds there as coming from that page, since a blog is often where the CMS shows itself.

Worked example. Say a store's homepage carries a WordPress generator tag (2 points) and loads files from /wp-content/ and /wp-includes/ (1 point each), plus scripts from /plugins/woocommerce/ (2 points). The result is WordPress at high confidence with 4 points, and WooCommerce listed underneath at medium confidence with 2. The Why we think so list under each card names the exact signals, and the small note under Other signals tells you whether you are seeing a fresh fetch or a cached result.

Limits worth knowing. The checker reads the HTML the server sends and does not run JavaScript, so anything a page injects in the browser is invisible to it (the same gap that JavaScript SEO deals with). It always checks the site's homepage, not the specific page you paste. A headless setup, where a CMS such as Contentful or Sanity feeds a framework, shows up as the framework, because the CMS never touches the HTML. A third-party script can add a misleading secondary match: a site using HubSpot only for marketing forms still loads HubSpot's script host and may list HubSpot CMS. Platforms outside the 17, such as Magento, show as Not identified. Results are cached for 7 days, so a site that migrated this week can still show its old platform.

Checking by hand. Open the page source (Ctrl+U, or Cmd+Option+U on a Mac) and search for "generator" first, then for telltale paths such as wp-content, cdn.shopify.com or _next/static. For headers, open your browser's developer tools, reload with the Network tab open, select the first document request and read its response headers. These are the same places this tool looks, and none of them is proof on its own: generator tags can be removed, asset paths rewritten and headers stripped by a proxy such as Cloudflare.

Knowing the platform is step one; publishing more and better content than the competitor running it is step two. Skribra integrates directly with WordPress, Shopify, Webflow, Notion and custom webhooks, so published articles land wherever your site already lives. See the full list of integrations, or the WordPress setup guide if the site you just checked runs on WordPress.