Auth.js / NextAuth
Auth Provider
Supabase Auth
Auth ProviderAuth.js / NextAuth vs Supabase Auth (2026): Which Is Better?
Auth.js / NextAuth and Supabase Auth are both popular choices, but they serve different needs. Auth.js / NextAuth is a Auth Provider with a traditional, manual approach to building, while Supabase Auth is a Auth Provider that prioritises developer or designer control.
Below you'll find a side-by-side breakdown of detection signals, AI scores, and technical fingerprints — plus our honest take on which builder wins for different use cases.
How we detect Auth.js / NextAuth vs Supabase Auth — see our methodology: AI Influence Score calculation, evidence tiers, and fingerprint signal types.
Side-by-Side Comparison
| | |
|---|---|---|
| Category | Auth Provider | Auth Provider |
| AI Score | 10/100 — Unknown | 10/100 — Unknown |
| Detection Signals | 2 patterns | 3 patterns |
| Script Detection | — | 1 patterns |
| CDN Detection | — | — |
| Header Detection | — | — |
| Sites Detected | No data yet | No data yet |
| Best For | Professional websitesTry Auth.js / NextAuth → | Professional websitesTry Supabase Auth → |
| Official Website | Visit | Visit |
Example Websites
Auth.js / NextAuth
Auth Provider
Auth.js / NextAuth is a auth provider with an AI Score of 10/100 (Unknown). Our detection engine uses 2 signal patterns to identify Auth.js / NextAuth-built sites.
Supabase Auth
Auth Provider
Supabase Auth is a auth provider with an AI Score of 10/100 (Unknown). Our detection engine uses 3 signal patterns to identify Supabase Auth-built sites.
Platform Overviews
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.
Supabase Auth
Supabase Auth is the authentication layer of the Supabase platform (an open-source Firebase alternative built on Postgres), providing email, social-login, and row-level-security-integrated user management for developers who also use Supabase's database and storage products. Our engine detects it through 1 script pattern and 2 HTML patterns tied to the Supabase client SDK's auth-session handling, distinct from — but related to — the signals used to detect Supabase's database product. Supabase can be self-hosted or used via its managed cloud; a detection doesn't distinguish between the two. Documented at supabase.com/auth.
Key Differences
- Both Auth.js / NextAuth and Supabase Auth are classified as Auth Provider tools, making them the most direct competitors in this comparison.
- Auth.js / NextAuth scores higher on AI involvement (10/100 vs 10/100 for Supabase Auth), meaning it relies more heavily on AI for site generation and content creation.
- Our detection engine identifies Auth.js / NextAuth using 2 fingerprint patterns and Supabase Auth using 3 patterns — more signals generally means more reliable detection.
Which Should You Choose?
Choose Auth.js / NextAuth if…
- You prefer a auth provider solution
- You want more manual control over the final output
- Auth.js / NextAuth's detection fingerprint of 2 signals means your site is reliably identifiable
Choose Supabase Auth if…
- You need a auth provider approach
- You prefer traditional building tools with predictable output
- Supabase Auth's ecosystem and community better match your team's existing workflow
Our Pick — Based on our detections
Auth.js / NextAuth
The most frequently detected auth provider in our scan database.
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