Tech Stack Detector
One of the free tools from KinetixSEO, an SEO and AI-citation (GEO) checker. This tool fetches any page and pattern-matches its HTML and response headers against known signatures to identify the CMS or website builder, the client-side JS framework, and the marketing/analytics tools it's running — the same kind of platform fingerprinting Wappalyzer and BuiltWith run at scale, but free and one page at a time. Knowing a site's stack matters whether it's your own (a CMS-specific SEO plugin recommendation only makes sense once you know the CMS) or a competitor's (planning a migration, or an agency scoping a pitch, both start with "what are they already running on").
Frequently asked questions
How does the tech stack detector actually work?
It fetches the public page once and matches its raw HTML and response headers against a library of known signatures — generator meta tags, script and CDN URLs, JS hydration markers (e.g. __NEXT_DATA__, data-v-* attributes), platform-specific response headers (X-Shopify-Id, X-Generator), and cookie names (wordpress_logged_in_*, joomla_user_state). A 'strong' signature (a generator meta tag, a vendor-specific header) is enough on its own to call something High confidence; a single 'moderate' signature (a CDN domain that could theoretically appear in a copied snippet) only reaches Low confidence, and needs a second moderate match to reach Medium. Nothing is guessed — if zero signatures match, that category is simply reported as not detected.
What can it detect, and what will it miss?
It detects the CMS/website-builder/ecommerce platform (WordPress, Shopify, Squarespace, Wix, Webflow, Drupal, Joomla, Ghost, HubSpot CMS), the client-side JS framework (Next.js, Nuxt, React, Vue, Angular — with version number when the page exposes one), and marketing/analytics tooling (Google Analytics, Google Tag Manager, Facebook Pixel, HubSpot tracking, Intercom, Drift, Segment — with the container/measurement/pixel ID extracted when it's a literal value in the static HTML). It will miss a fully custom, homegrown stack with no public fingerprint, anything injected only after a user interaction or behind a login wall, and the backend language or server framework when nothing in the HTML or headers reveals it — this is static-page fingerprinting, not a network or infrastructure scan.
Why would I want to know a competitor's tech stack?
It's useful competitive research: seeing what CMS or platform competitors in your niche settled on tells you what a realistic migration target looks like, which marketing/analytics tools they're running tells you what they're measuring, and — if you're an agency — knowing a prospect's current stack before a pitch call means you show up already speaking their language instead of asking basic discovery questions.
Is it legitimate to check another site’s tech stack this way?
Yes. This reads only what every visitor's browser already receives when it loads the page — the same public HTML and response headers visible in any browser's "View Source" or DevTools network tab. There's no login bypass, no crawling beyond the single page you enter, and no exploitation of anything — it's the same publicly-available fingerprinting approach tools like Wappalyzer and BuiltWith have run at scale for years.
Do you store the URL I check, or share this data?
We fetch only the page you submit — no signup or account required. Results are cached briefly by domain so a repeat check on the same site returns instantly instead of re-fetching, but we don't sell this data, attach it to your identity, or share it with third parties.
This is one check from KinetixSEO's full SEO/GEO audit. Want the complete picture — Core Web Vitals, AI-citation readiness, technical SEO health, and tailored fixes? Run the free full checker.