Auth Provider

Is This Website Built With Auth.js / NextAuth?

Auth.js (formerly NextAuth.js) is an open-source authentication library built primarily for Next.js and other JavaScript frameworks, letting developers add login (OAuth providers, email, credentials) without a paid third-party identity platform. Our engine detects it through 2 HTML patterns tied to its default sign-in page markup and session-cookie conventions, since as a self-hosted library it doesn't load from an external CDN the way hosted identity platforms do. A detection indicates the site handles its own auth backend using this library rather than outsourcing it. Documented at authjs.dev.

Detect Auth.js / NextAuth Websites — Free Tool

Enter any URL to check if it was built with Auth.js / NextAuth. Instant results, no account required.

How we detect Auth.js / NextAuth — see our methodology: AI Influence Score calculation, evidence tiers, and fingerprint signal types.

How to Detect Auth.js / NextAuth Websites

HTML Patterns

2 patterns

3 patterns

1. Check the Page Source

Open the website in your browser, right-click, and select "View Page Source". Search for auth.js / nextauth-specific patterns in the HTML.

4. Use AI Website Detector (Easiest)

Our automated scanner checks all these signals at once and gives you an instant confidence score. Just enter any URL above.

Frequently Asked Questions

Is this website built with Auth.js / NextAuth?

You can detect if any website was built with Auth.js / NextAuth by using our free scanner above. Just enter the URL and we'll analyze HTML patterns, JavaScript files, CDN domains, and HTTP headers to determine if Auth.js / NextAuth was used — with a confidence score.

How to detect if a website was built with Auth.js / NextAuth?

There are several ways to detect Auth.js / NextAuth: (1) View the page source and look for Auth.js / NextAuth-specific class names or script URLs, (2) Check the Network tab in DevTools for requests to Auth.js / NextAuth CDN domains, (3) Use our free tool — we check 2 detection signals automatically.

What websites are built with Auth.js / NextAuth?

Auth.js / NextAuth is used by thousands of websites worldwide. Our scanner has detected many Auth.js / NextAuth-built sites across different industries. You can scan any URL to check if it uses Auth.js / NextAuth.

How accurate is the Auth.js / NextAuth detection?

Our Auth.js / NextAuth detection engine checks 2 unique fingerprint signals, achieving high confidence results. We score each match and return a confidence percentage so you know how certain the detection is.