About
Clerk is a user management platform.
Categories: Authentication
Quick facts
Detection methodology for Authentication
Auth providers expose a script SDK and (usually) a hosted login endpoint. Auth0's `@auth0/auth0-spa-js` plus `*.auth0.com` redirects; Clerk's `@clerk/clerk-js` plus `clerk.<account>.lcl.dev`; NextAuth's `next-auth` package plus the `/api/auth/...` route handler. We catch each via the bundle and the network requests, plus the exact SDK version from the sourcemap.
How we detect Clerk
Each signal alone is rarely conclusive — Sourcemap Explorer cross-references all of them and weights by confidence. You can reproduce any of these checks yourself in Chrome DevTools.
Window-level global the technology installs on page. Reproducible by typing the path into the DevTools console.
window.Clerk.authenticateWithMetamask
window.Clerk.openSignIn
window.Clerk.version = ([\d\.]+)
FAQ
How do I check if a website is using Clerk?
Open the page in Chrome, click the Sourcemap Explorer toolbar icon, and read the Stack tab. The popup matches Clerk's fingerprint signals (response headers, asset URL prefixes, runtime globals, sourcemap paths) and flags it whenever any combination is found. The same checks can be reproduced manually in DevTools — see the "How we detect" section above.
What Clerk version can Sourcemap Explorer detect?
Clerk ships as a hosted authentication 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 Clerk a SaaS or self-hosted?
Clerk is offered as a hosted SaaS product. Detection runs against the JavaScript SDK or asset-URL fingerprints the platform ships into pages.
How much does Clerk cost?
Clerk's pricing model is documented as: mid, recurring. Detection is independent of the pricing tier — Sourcemap Explorer flags the technology by its fingerprints, regardless of which paid plan a site is on. See the official site for the current pricing page.
Where can I read more about Clerk?
Official site: https://clerk.dev. For Sourcemap Explorer's detection guide, see the deep-dive link below or the related guides in the cross-link section.
Keep reading on Sourcemap Explorer
Practical guides
Detected by Sourcemap Explorer
Open the popup on any page running Clerkand you'll see the exact version pulled from the bundled package.json when sourcemaps are exposed.