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Competitive Research May 6, 2026 6 min read

How to Find Out What Website Builder Any Site Uses

Whether you're scoping a competitor, pitching a redesign, or just curious — identifying the platform behind any website takes about 10 seconds if you know what to look for.

Every website is built on something. Webflow, Framer, WordPress, Wix, Squarespace, Shopify, a custom React app, a static site generator — each one leaves a distinct set of fingerprints in the HTML, JavaScript, and network requests that make up a page. Those fingerprints are readable by anyone, no developer access required.

The reasons to care are practical: if you're a web designer or agency, knowing your prospect's current platform tells you the scope of a migration before you quote. If you're a founder, knowing your competitor switched from WordPress to Webflow signals a brand reposition or funding round. If you're a developer evaluating tools, seeing what a site you admire is built on is the fastest form of social proof.

The Fastest Method: One-Click Detection

The most efficient way to identify what website builder a site uses is SaaS Detective — a free Chrome extension that runs automatically when you open its popup on any page. It checks for Site Builder signatures (Webflow, Framer, Wix, Squarespace, Webflow), CMS platforms (WordPress, Ghost, Drupal), and frameworks (Next.js, Nuxt, Astro) in a single scan. No source code, no digging — just open the extension and read the results.

For anything more manual, the methods below work without any tools installed.

Signal 1: View Page Source

Right-click any page and select "View Page Source" (or press Ctrl+U / Cmd+U). Then search for these platform-specific strings:

This works reliably for most sites, but some platforms are intentionally obscured — custom domains, self-hosted WordPress installs, or headless configurations strip out the obvious tells. For those, you need to go deeper.

Signal 2: Network Requests and Asset URLs

Open Chrome DevTools (F12), go to the Network tab, and reload the page. Filter by "JS" and look at where scripts are loaded from. The CDN domain almost always gives away the platform:

Even if a company uses a custom domain for assets, the file path patterns are almost always platform-specific. Webflow's generated class names follow a predictable format. WordPress themes consistently use /wp-content/themes/[theme-name]/. Squarespace injects a unique JSON configuration block into every page.

Website builders leave fingerprints everywhere — in asset CDN URLs, generated class names, HTML comments, and meta tags. You just need to know which fingerprint belongs to which platform.

Signal 3: Meta Tags and Generator Tags

Many platforms inject a <meta name="generator"> tag into the HTML head. Search the page source for generator:

Not all platforms add this tag, and some remove it intentionally for SEO reasons (it's generally considered low-value). But when it's present, it's the most direct answer you'll find.

Signal 4: URL Structure and Routing Patterns

The URL patterns of a site often reveal its platform, especially for e-commerce and CMS-heavy sites:

This is especially reliable for e-commerce. A site with /collections/all or /products/ in its navigation is almost certainly Shopify. BigCommerce uses /categories/. WooCommerce (running on WordPress) keeps WordPress URLs but adds /shop/ and /product/ paths.

Quick Identification Workflow

Navigate to the site, open SaaS Detective, and check the Site Builders and Frameworks categories first. If you need to verify manually, hit Ctrl+U and search for webflow, framer, wp-content, or squarespace. You'll have your answer in under 30 seconds on almost any site.

Signal 5: Performance and Technical Tells

Some platform characteristics show up in the page's technical profile rather than its source code:

Webflow pages load a large JavaScript runtime file called webflow.js that handles interactions, animations, and form submissions. Even if asset URLs are masked, this file is almost always present on Webflow sites.

Framer sites use React under the hood and their pages are rendered as Single Page Applications. The initial HTML is minimal; most content is injected by JavaScript. If you view source and see very little HTML content but a large <script> tag loading from framer.com, it's Framer.

Next.js sites — whether custom-built or via Vercel — include a __NEXT_DATA__ JSON block in the page source and load scripts from /_next/static/ paths. This tells you it's a React/Next.js application, though it doesn't tell you whether it's custom-built or on a platform like Builder.io or Contentful.

Wix has a distinctive rendering approach where most page content is inside a deeply nested iframe structure within the main document. If a site feels slightly sluggish on first load and inspecting the DOM reveals an unusual iframe hierarchy, Wix is a strong candidate.

What Website Builder Choice Tells You

Beyond pure curiosity, the platform a site runs on is a signal about the team behind it:

For agencies pitching a redesign, this framing matters: a company on Wix with a 5-year-old design is a completely different conversation than a company on a custom Next.js app that clearly has in-house developers. The first needs a new platform; the second needs to be convinced the investment is worth pulling their engineers off product work.

Bottom Line

Identifying what website builder a site uses is almost always a one-minute task if you know where to look. View source for generator tags and CDN URLs. Check the Network tab for asset origin domains. Look at URL structure for platform-specific routing patterns. For the fastest workflow, SaaS Detective automates all of this — it detects Webflow, Framer, Wix, Squarespace, WordPress, Ghost, and 200+ other tools the moment you open the popup on any page. No source code required.

Identify Any Site's Stack Instantly

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