Whether you are researching a competitor, evaluating a potential client's site, or simply curious about how a website was built, knowing the CMS (content management system) behind it is incredibly valuable. CMS detection reveals the foundation a site is running on — WordPress, Shopify, Wix, Squarespace, Drupal, or one of hundreds of other platforms.
In this guide, we cover five reliable methods you can use right now to figure out what CMS any website is using.
1. View the Page Source
The fastest low-tech method is viewing the HTML source of a page. Right-click anywhere on the website and select View Page Source (or press Ctrl+U /Cmd+Option+U).
Once you have the source open, look for these tell-tale signs:
- WordPress: Search for
/wp-content/or/wp-includes/. Nearly every WordPress site loads stylesheets and scripts from these directories. You may also find a<meta name="generator" content="WordPress 6.x">tag in the<head>. - Shopify: Look for
cdn.shopify.comin script or stylesheet URLs, orShopify.themein inline JavaScript. - Wix: Wix sites typically load resources from
static.parastorage.comorstatic.wixstatic.com. - Squarespace: Check for
squarespace.comin the source or thedata-squarespace-ui-typeattribute on elements.
This method works well for popular CMS platforms, but it requires manual searching and knowledge of what patterns to look for. Less common platforms may not have obvious fingerprints in the HTML.
2. Check HTTP Response Headers
HTTP headers reveal a surprising amount about a site's technology. Open your browser's DevTools (F12), navigate to the Network tab, reload the page, and click on the main document request to inspect the response headers.
Key headers to watch for:
- X-Powered-By: Often reveals the CMS or framework directly, such as
X-Powered-By: ExpressorX-Powered-By: PHP/8.2. - Server: Shows the web server software (Apache, Nginx, LiteSpeed). While not a CMS indicator on its own, it narrows down the stack.
- X-Drupal-Cache or X-Generator: Drupal: Drupal-specific headers that confirm the CMS immediately.
- Set-Cookie: Cookie names like
wp_,_shopify_s, orCRAFT_CSRF_TOKENpoint directly to their respective CMS platforms.
3. Analyze URL Patterns and Site Structure
The way a website structures its URLs can be a strong clue. Each CMS has default URL conventions:
- WordPress:
/wp-admin/,/wp-login.php,/?p=123(default permalink format) - Shopify:
/collections/,/products/,/cart - Drupal:
/node/123,/user/login - Joomla:
/administrator/,/index.php?option=com_content
Try appending common admin paths to the domain. If example.com/wp-admin/ redirects to a WordPress login page, you have your answer.
4. Use an Online Detection Tool
The most efficient method is using a purpose-built technology detection tool. WhatStack scans any URL and returns a complete technology profile in seconds — not just the CMS, but the entire stack including JavaScript frameworks, analytics, hosting, ad tech, and more.
Unlike manual inspection, automated tools analyze multiple data sources simultaneously: HTTP headers, HTML patterns, script URLs, cookies, DNS records, and even ads.txt files. This catches technologies that are invisible in the page source alone.
Other online tools in this space include BuiltWith, Wappalyzer, and WhatCMS, each with different strengths. For a quick, free CMS check, an online tool is almost always the fastest path to an answer.
5. Install a Browser Extension
If you find yourself checking website technologies frequently, a browser extension can save time. Extensions like Wappalyzer sit in your toolbar and display detected technologies on every page you visit.
The advantage of extensions is convenience — you see the tech stack passively as you browse. The downside is that they only analyze what is visible on the current page and may miss server-side technologies, DNS-based signals, or ads.txt data that a full scanner would catch.
Which Method Should You Choose?
For a one-off check, viewing the page source or using an online scanner like WhatStack is the fastest approach. If you need to analyze websites regularly — for lead generation, competitive research, or client audits — an API-based tool gives you the most comprehensive and automatable results.
Want to try it right now? Enter any URL in the WhatStack scanner and see the full technology profile in seconds. You can also browse our technology directory to see all 8,000+ technologies we detect, including detailed pages for platforms like WordPress, Shopify, and Wix.