CMS detector
Works on any public site. We only read what a visitor's browser receives.
How to use the CMS detector
Enter a website and the detector tells you what it is built with: the content management system, website builder or framework, plus hosting, CDN and the tags it loads. It works on any public site, not only your own.
Enter any site
Type a domain, or paste a full page address if the part you care about lives somewhere else, such as /blog/.
We read the page
One request, made like a browser's: response headers, cookies, generator tags, asset paths and inline scripts.
We match fingerprints
Each platform leaves its own marks. Every match is listed with the exact line we found, so you can check it.
WordPress gets a deep dive
On WordPress we read the theme's style.css header, name the parent theme and list the plugins the page loads.
Every result shows its evidence. If the detector says WordPress, it shows you the generator tag or the /wp-content/ path it found, and you can open view source and see the same line. We never report a platform from a guess.
What the CMS detector results mean
What it's built with
The platform answer, with up to three pieces of evidence each. A site can show more than one: WordPress with WooCommerce, or Next.js in front of a headless CMS.
WordPress theme and setup
The active theme from its style.css header, the parent theme if it is a child theme, the WordPress version, page builder, SEO plugin and caching plugin.
Hosting, CDN and tags
Only hosts that stamp their own response headers, such as Cloudflare's cf-ray or Vercel's x-vercel-id. Analytics and pixels appear under Also found.
"We couldn't match this site" is an honest answer, not an error. It means no fingerprint we know appeared and WordPress's own paths did not answer. When a security check answers instead of the site, the detector says so rather than guessing.
How to tell what CMS a website uses manually
Every detector reads the same public clues you can read yourself. Open the site, press Ctrl+U (Cmd+Option+U on a Mac) to view source, and search the page.
1. The generator tag. Search for generator. WordPress, Drupal, Joomla, Ghost, Wix, Webflow, Hugo and many others write their name, and often their version, into a meta tag.
2. Asset paths. Search for the folders platforms load files from: /wp-content/ for WordPress, cdn.shopify.com for Shopify, /_next/ for Next.js.
3. The REST API. Add /wp-json/ to the domain. A WordPress site answers with a page of JSON naming its routes, even when the homepage hides everything else.
4. Response headers. In your browser's developer tools, open the Network tab, reload, and click the first request. Headers like x-generator: Drupal 11, x-shopid or x-wix-request-id name the platform outright.
<meta name="generator" content="WordPress 6.8.3"> <link rel="https://api.w.org/" href="https://example.com/wp-json/"> <link rel="stylesheet" href="https://example.com/wp-content/themes/astra/style.min.css?ver=4.8.1"> <script src="https://example.com/wp-content/plugins/elementor/assets/js/frontend.min.js?ver=3.25.4"></script>
| Platform | What to look for |
|---|---|
| WordPress | /wp-content/ and /wp-includes/ in asset URLs, a generator tag reading WordPress, a /wp-json/ link |
| Shopify | cdn.shopify.com assets, a Shopify.theme script, a powered-by: Shopify header |
| Wix | static.wixstatic.com and parastorage.com assets, an x-wix-request-id header |
| Squarespace | static1.squarespace.com assets, the comment <!-- This is Squarespace. --> |
| Webflow | a Webflow generator tag, data-wf-page attributes, website-files.com assets |
| Drupal | a Drupal generator tag or x-generator header, drupal-settings-json, /sites/default/files/ |
| Joomla | a Joomla! generator tag, /media/system/js/, /templates/<name>/ |
| HubSpot CMS | a HubSpot generator tag, x-hs-hub-id and x-hs-content-id headers |
| Next.js, Nuxt, Gatsby | /_next/static/, /_nuxt/, a ___gatsby root element |
Is this site WordPress? How to check if a website is WordPress
WordPress is the platform you are most likely to find. W3Techs counts it on 39.6% of all websites, a 58.3% share of the sites whose CMS it can identify (W3Techs, 20 October 2026).
The quickest checks are /wp-content/ in view source and /wp-json/ answering with JSON. Hardened sites remove the generator tag and some rename their folders, so the detector also asks WordPress-only paths directly: the REST API, the core block stylesheet, a guarded wp-login.php, and installs in a subfolder such as /blog/. It uses the same WordPress detection as our AI readiness checker, so the two never disagree about a site.
Sites on WordPress.com are WordPress too. The detector reads WordPress.com's own response headers to tell you whether the plan allows plugins.
WordPress theme detector: what WordPress theme is that site using?
Every WordPress theme lives in its own folder, and every theme folder has a style.css whose opening comment names the theme. That header is the most reliable answer there is.
To find it by hand, search view source for /wp-content/themes/. The word after it is the theme folder. Open /wp-content/themes/folder-name/style.css and read the top of the file: Theme Name, Theme URI, Author and Version.
If the header has a Template: line, you are looking at a child theme. A child theme holds a site's customizations and borrows everything else from the parent theme named in Template, so the parent is usually the theme you would buy or download. The detector reads both headers and shows them side by side.
/* Theme Name: Astra Child Template: astra Version: 1.0.0 Author: Example Agency Text Domain: astra-child */
When the theme is listed in the wordpress.org directory, the detector links its page there. Premium and custom themes have no listing, and an agency's custom theme often carries the agency's name rather than a product name. Page builders such as Elementor, Divi and Bricks blur the line further, since the builder draws most of what you see; read our notes on page builders and AI search.
WordPress plugin detector: which plugins can you see from outside?
Plugins that load CSS or JavaScript on the page show up as /wp-content/plugins/plugin-name/ paths. The detector lists every folder it finds, names it, and links its wordpress.org page when there is one.
Some plugins also sign the HTML. Yoast SEO, Rank Math and All in One SEO leave a comment in the head; WP Rocket, LiteSpeed Cache and W3 Total Cache leave one at the end of the page. That is how the detector names the SEO and caching plugin even when no plugin folder is loaded.
What it cannot see: plugins that only work in the admin (backups, security scanners, redirects), plugins that only load on other pages, such as a form on the contact page, and anything a caching plugin merges into one combined file. To check a different page, paste its full address.
Why a CMS detector can miss what a site runs on
Headless setups
The CMS stores content and a framework such as Next.js builds the pages. Visitors never touch the CMS, so only the framework shows, unless images still load from the CMS.
Hidden generator tags
Removing the generator tag and version numbers is a common hardening step. The detector falls back to asset paths, headers and the REST API, and says when the version is hidden.
Security plugins and bot walls
Some plugins rename /wp-content/, and some firewalls show servers a security check instead of the page. When that happens we say we couldn't see, instead of guessing.
Custom themes and builds
A theme written from scratch has no public name, and a fully custom site has no platform fingerprint at all. The detector reports what the files say, nothing more.
What each CMS means for AI search readiness
ChatGPT, Claude, Perplexity and Google's AI Overviews can only recommend what their crawlers can read. The platform decides how much of that you control.
WordPress
You control the HTML, the schema markup and robots.txt, and plugins can change all three. LovedByAI is a WordPress plugin built for exactly this: it makes a site readable and recommendable by AI assistants without touching the design.
Shopify, Wix, Squarespace, Webflow
The platform writes much of the markup. You can edit titles, descriptions and content, but deeper changes to structured data or crawler rules depend on what the builder allows.
Headless and JavaScript frameworks
AI crawlers read the HTML the server sends. Content that only appears after JavaScript runs in a browser is at risk of being missed, so server-side rendering matters.
Whatever the platform, the questions are the same: can AI crawlers reach the page, can they read it, and does it say clearly who you are. The free AI readiness check answers all three, and the meta tag checker covers the titles and descriptions AI answers quote.
Checking your own WordPress site?
If the detector shows your theme and plugins, it shows them to everyone. That is normal and not a security problem in itself. What matters more is whether AI crawlers can read what you want them to; our robots.txt checker tests that for GPTBot, ClaudeBot and PerplexityBot.
CMS detector and WordPress theme detector FAQ
01How do I find out what CMS a website is using?
Enter the address in the CMS detector above. It reads the page the way a browser does and matches generator tags, asset paths, response headers and cookies against the platforms it knows, then shows the exact evidence for each match. To check by hand, view source and search for "generator", "wp-content", "cdn.shopify.com" or "wixstatic".
02How do I find out what WordPress theme a site is using?
Search the page source for /wp-content/themes/. The word after it is the theme folder. Open /wp-content/themes/folder-name/style.css on the same site and read the comment at the top, which names the theme, its author and version. The detector does this for you and also follows the Template line to the parent theme when the site uses a child theme.
03What does it mean when a WordPress theme is a child theme?
A child theme holds a site's own customizations and inherits everything else from a parent theme. Its style.css has a Template line naming the parent's folder. If you want the same look, the parent theme is usually the one to get, since the child theme is specific to that site.
04How can I check if a website is WordPress?
Look for /wp-content/ or /wp-includes/ in the page source, or add /wp-json/ to the domain and see whether it answers with JSON. If neither works, the site may hide its tracks. The detector also checks the core block stylesheet, a guarded wp-login.php and common subfolders such as /blog/, the same checks our AI readiness checker uses.
05Can a WordPress plugin detector see every plugin?
No detector can. Only plugins that load files or leave comments on the page you check are visible from outside. Admin-only plugins such as backup, security and redirect tools leave no trace on the front end, and plugins that only load on certain pages show up only there. Caching plugins that combine files can hide the rest.
06Why can't the detector see what a site runs on?
Usually because a firewall shows visitors from servers a security check instead of the page, which tells us nothing about the CMS behind it. The detector says so rather than guessing. It can also happen when a site is custom-built, runs headless behind a JavaScript framework, or strips every platform fingerprint.
07What is this website built with if no CMS shows up?
Often a JavaScript framework such as Next.js, Nuxt or Gatsby, which the detector names when it finds one. Those sites may still pull their content from a CMS through an API, which is called a headless setup. The CMS is then invisible from outside unless images or files still load from its servers.
08Does the CMS a site uses affect AI search?
It affects how much you can change. AI assistants like ChatGPT, Claude and Perplexity read the HTML a site serves, so what matters is whether the content, headings and structured data are there and readable. WordPress lets you control all of it through plugins, while hosted builders decide more of the markup for you.
More free AI search tools
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Sitemap checker
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Schema markup generator
Build valid JSON-LD for your page, prefilled from the page itself.
Now see how AI reads the site
Knowing the platform is step one. The free AI readiness check shows whether ChatGPT, Claude and Perplexity can reach, read and recommend it.
Run the free AI readiness check