What CMS Is This Website Using? 4 Ways to Check (Free)

You land on a website and want to know how it was built. Maybe you are pitching a redesign, sizing up a competitor, or you simply inherited a site and nobody remembers what it runs on. The question is always the same: what CMS is this website using?

There are four reliable ways to find out, from a one-click checker to reading the source code yourself. Here is each one, with the exact signatures to look for.

Method 1: Use a free CMS checker (fastest)

Paste the URL into our free CMS checker and press "Check site". It fetches the public homepage, fingerprints the HTML, scripts and response headers, and names the CMS: WordPress, Wix, Shopify, Squarespace, Webflow, Joomla, Drupal and many more, with the version when the site exposes it.

It also lists the rest of the technology stack (framework, analytics, hosting, CDN, web server), which matters when the CMS itself is hidden. No signup, no browser extension, and no access to the site is needed.

Used to BuiltWith or Wappalyzer? We compare the free options in BuiltWith & Wappalyzer alternatives.

Method 2: View the page source and look for signatures

Every CMS leaves fingerprints in the HTML: folder names, asset domains, CSS classes. Right-click the page, choose View page source (or press Ctrl+U / Cmd+Option+U), then search with Ctrl+F for these strings:

One match is usually enough. WordPress sites also reveal their theme and plugins here: the folder name after /wp-content/themes/ is the theme.

Method 3: Check the generator meta tag

Many platforms add a <meta name="generator"> tag to the page head. Search the source for generator and you may see something like:

• WordPress 6.6: WordPress, including the exact version
• Wix.com Website Builder: Wix
• Joomla! - Open Source Content Management: Joomla
• Drupal 10 (https://www.drupal.org): Drupal
• Ghost 5.x: Ghost
• Webflow: Webflow

Security plugins often strip this tag, so a missing generator does not mean "custom site". Fall back to method 2 or 4.

Method 4: Try the admin URL and other clues

Login paths are a quick tell. Add these to the domain and see what loads:

• /wp-admin or /wp-login.php: a WordPress login screen means WordPress.
• /administrator: the Joomla admin login.
• /user/login: the default Drupal login.
• /admin redirecting to a Shopify login: a Shopify store.

Other clues: the favicon (default Wix and Squarespace icons are recognizable), the robots.txt file (WordPress sites often disallow /wp-admin/), and the footer ("Powered by Squarespace", "Made with Webflow").

Why a CMS checker sometimes says "unknown"

If none of the methods above find anything, the site is probably one of these:

• Custom-built: a framework like Next.js, Laravel or Rails with no off-the-shelf CMS. The tech stack list will still show the framework.
• Headless: content lives in a headless CMS (Contentful, Sanity, Strapi) and the front end is a separate app, so the CMS never appears in the HTML.
• Hidden or blocking: the site strips signatures or blocks automated requests.

What's my CMS? (for your own website)

If it is your own site and you are not sure what it runs on, the answer is usually in how you log in. A /wp-admin login means WordPress. If you edit the site inside a Wix, Squarespace, Shopify or GoDaddy dashboard, that is your CMS. Still unsure? Enter your domain in the CMS checker, or check your hosting invoice: managed WordPress hosts name it on the bill.

Why agencies check the CMS before pitching

For a web design or SEO agency, the CMS is a sales signal:

• An outdated WordPress version or an abandoned theme means security risk and a clear reason to rebuild.
• A templated Wix or GoDaddy site usually means a small business that outgrew its DIY site.
• No site at all is the strongest signal of all. See how to find businesses without a website.

Checking sites one by one works for a handful of prospects. LeadWebia runs the CMS check, PageSpeed audit and website-status check on every local business it finds, so you can filter a whole city by stack. The free plan includes 50 leads, no credit card.