shadcn/ui
shadcn/ui is a component system built with Radix UI and Tailwind CSS.
What detecting shadcn/ui tells you about a site
shadcn/ui is not a dependency you install but a collection of components you copy into your own codebase, built on Radix primitives and styled with Tailwind. That copy-in model makes it a DOM-signature detection: Radix's data-radix-* and data-state attributes combined with shadcn's characteristic Tailwind class strings and CSS variable tokens (--background, --foreground, bg-primary). Spotting it tells you a React team that wanted full ownership of its component code and design system rather than a black-box library — a very common, design-conscious modern front-end choice.
The detail that matters for shadcn/ui
Because shadcn/ui is copied into the codebase rather than installed, there's no `node_modules/` path and no package version to read — it's a structural detection, not a dependency one. What you can date instead is the Radix and Tailwind underneath, and whether the newer CSS-variable theming (`hsl(var(--background))`) or the older hard-coded token style is in use, which roughly brackets when the components were scaffolded.
shadcn/ui in a real-world stack
When you find shadcn/ui, it rarely travels alone. React (very often Next.js) with Tailwind CSS, Radix UI underneath, and frequently Lucide icons and the cn/clsx class helper.
About
shadcn/ui is a component system built with Radix UI and Tailwind CSS.
Categories: UI frameworks
Quick facts
Implies
When shadcn/uiis detected, Sourcemap Explorer also marks the following technologies as present (Wappalyzer's implies graph).
FAQ
How do I check if a website is using shadcn/ui?
Open the page in Chrome, click the Sourcemap Explorer toolbar icon, and read the Stack tab. shadcn/ui's fingerprints span response headers, asset URL prefixes, runtime globals and sourcemap paths, and the popup flags shadcn/ui whenever any combination of them is found. The same checks can be reproduced manually in DevTools — see the "How we detect" section above.
What shadcn/ui version can Sourcemap Explorer detect?
shadcn/ui ships as a hosted ui frameworks rather than a bundled npm package, so version-specific detection isn't always possible. Where the platform leaks a version in response headers (`X-Powered-By`, `Server`, generator meta tags) we surface it; otherwise we report presence only.
Is shadcn/ui open source?
Yes, shadcn/ui is open source. The license details are listed on the official site (https://ui.shadcn.com), and the codebase typically lives on a public source-control host.
Where can I read more about shadcn/ui?
Official site: https://ui.shadcn.com. For Sourcemap Explorer's detection guide, see the deep-dive link below or the related guides in the cross-link section.
Detected by Sourcemap Explorer
Open the popup on any page running shadcn/uiand you'll see the exact version pulled from the bundled package.json when sourcemaps are exposed.