# Authentication for developers: which vendors AI models recommend (September 2026)

Source: Memetik Index, https://www.memetik.ai/index/developer-auth
Field: Startup stack. Edition: 2026-09. Run: 2026-09-02.
Method: 5 fixed buyer prompts sent once each to 10 current models (GPT-5.6 Sol, GPT-5.6 Terra, GPT-5.6 Luna, Claude Opus 5, Claude Sonnet 5, Claude Fable 5, Gemini 3.6 Flash, Gemini 3.5 Flash, Sonar Pro, Sonar Reasoning Pro) via their APIs with web search enabled. 50 answers. Answer share = fraction of answers naming the vendor. Named first = fraction where it was the first tracked vendor named.

**Clerk leads** with 98% answer share (named in 49 of 50 answers) and was named first in 58%. Auth0 follows at 94%. 17 vendors were named at least once.

## Answer share

| # | Vendor | Answer share | Named first | Mentions | Models |
|---|---|---|---|---|---|
| 1 | Clerk | 98% | 58% | 49/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 2 | Auth0 | 94% | 8% | 47/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 3 | WorkOS | 80% | 18% | 40/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 4 | Supabase Auth | 74% | 0% | 37/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 5 | Firebase Auth | 42% | 2% | 21/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 6 | AuthKit | 36% | 0% | 18/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Gemini, Gemini 3.5 Flash |
| 7 | Kinde | 34% | 8% | 17/50 | Claude Opus 5, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 8 | PropelAuth | 30% | 0% | 15/50 | Claude Opus 5, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 9 | NextAuth / Auth.js | 28% | 4% | 14/50 | GPT-5.6 Sol, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 10 | Stytch | 28% | 0% | 14/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude, Gemini, Perplexity, Sonar Reasoning Pro |
| 11 | Better Auth | 26% | 2% | 13/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 12 | Keycloak | 26% | 0% | 13/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude Fable 5, Gemini, Perplexity, Sonar Reasoning Pro |
| 13 | AWS Cognito | 20% | 0% | 10/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude, Claude Fable 5, Perplexity, Sonar Reasoning Pro |
| 14 | Descope | 14% | 0% | 7/50 | GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Perplexity, Sonar Reasoning Pro |
| 15 | Frontegg | 14% | 0% | 7/50 | Claude Opus 5, Claude, Claude Fable 5, Sonar Reasoning Pro |
| 16 | FusionAuth | 10% | 0% | 5/50 | Claude, Claude Fable 5, Gemini, Perplexity, Sonar Reasoning Pro |
| 17 | Ory | 2% | 0% | 1/50 | Sonar Reasoning Pro |

## By model

- **GPT-5.6 Sol** (OpenAI, gpt-5.6-sol, 5 answers): Clerk 100%, WorkOS 100%, AuthKit 100%, Auth0 80%, Supabase Auth 80%
- **GPT-5.6 Terra** (OpenAI, gpt-5.6-terra, 5 answers): Clerk 100%, Auth0 100%, WorkOS 80%, AuthKit 80%, Supabase Auth 60%
- **GPT-5.6 Luna** (OpenAI, gpt-5.6-luna, 5 answers): Clerk 100%, Auth0 100%, Supabase Auth 80%, Firebase Auth 80%, WorkOS 60%
- **Claude Opus 5** (Anthropic, claude-opus-5, 5 answers): Clerk 100%, Auth0 100%, WorkOS 80%, Supabase Auth 80%, Kinde 80%
- **Claude Sonnet 5** (Anthropic, claude-sonnet-5, 5 answers): Clerk 100%, Auth0 100%, Supabase Auth 80%, Firebase Auth 80%, WorkOS 60%
- **Claude Fable 5** (Anthropic, claude-fable-5, 5 answers): Clerk 100%, Auth0 100%, WorkOS 60%, Supabase Auth 60%, Firebase Auth 60%
- **Gemini 3.6 Flash** (Google, gemini-3.6-flash, 5 answers): Clerk 100%, Auth0 100%, WorkOS 100%, Supabase Auth 100%, PropelAuth 100%
- **Gemini 3.5 Flash** (Google, gemini-3.5-flash, 5 answers): Clerk 100%, Auth0 100%, WorkOS 100%, Supabase Auth 100%, AuthKit 60%
- **Sonar Pro** (Perplexity, sonar-pro, 5 answers): Clerk 100%, Auth0 80%, WorkOS 80%, Supabase Auth 40%, Firebase Auth 40%
- **Sonar Reasoning Pro** (Perplexity, sonar-reasoning-pro, 5 answers): Clerk 80%, Auth0 80%, WorkOS 80%, Supabase Auth 60%, Keycloak 60%

## Sources the models cited

- kinde.com: 99
- propelauth.com: 88
- workos.com: 83
- merginit.com: 80
- ssojet.com: 47
- designkey.studio: 47
- spiderhunts.com: 40
- reddit.com: 34
- clerk.com: 31
- boilerplatehub.com: 31
- pkgpulse.com: 27
- dev.to: 26
- auth0.com: 21
- mojoauth.com: 20
- makerkit.dev: 20

## Prompts

1. What is the best authentication provider for a new SaaS app? Name specific products.
2. Which auth service should I use for a Next.js startup?
3. Compare the top user authentication platforms for startups.
4. I'm building a B2B app and need SSO and user management. What do you recommend?
5. Best managed auth for a startup that wants to avoid building login itself?

## Tracked but never named

None.

Raw answers: https://www.memetik.ai/index/developer-auth (every answer published in full). Chart image: https://www.memetik.ai/charts/developer-auth.png. Licence: CC BY 4.0, credit "Memetik Index".