# Auth0 vs Clerk: which do AI models recommend for CIAM, October 2026

IT AI Recommendation Index, October 2026 Edition, Customer identity and access management. Five of fourteen models named Auth0 first on the direct prompt; three named Clerk. Page: https://it-ai-index.com/identity/customer-identity-and-access-management/auth0-vs-clerk/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| Auth0 | 18% | #2 of 14 | 22% | 60 | 14 of 14 |
| Clerk | 18% | #3 of 14 | 3% | 31 | 12 of 14 |

## The direct prompt, model by model

- Qwen 3.7 Flash: both first (first choices: Auth0, Clerk) (alternatives: Microsoft Entra ID)
- MiniMax M2.5: both first (first choices: Auth0, Clerk) (alternatives: Descope, LoginRadius)
- Grok 4.1 Fast: auth0 first (first choices: Auth0) (alternatives: Clerk, Frontegg, FusionAuth, Microsoft Entra External ID, Stytch, WorkOS)
- DeepSeek V4 Flash: auth0 first (first choices: Auth0, Frontegg) (alternatives: Clerk, Microsoft Entra External ID, Stytch)
- GLM 4.7 FlashX: auth0 first (first choices: Auth0) (alternatives: Clerk, Descope, LoginRadius, Microsoft Entra External ID)
- Kimi K2: clerk first (first choices: Clerk, Frontegg) (alternatives: FusionAuth, WorkOS)
- Gemini 3.5 Flash: neither first, one named (first choices: WorkOS) (alternatives: Clerk, Frontegg, Kinde)
- Perplexity Sonar: neither first, one named (first choices: LoginRadius) (alternatives: Clerk, Frontegg, Microsoft Entra External ID)
- Llama 4 Maverick: neither first, one named (first choices: LoginRadius) (alternatives: Clerk, OneWelcome Identity Platform)
- GPT-6 Luna: neither first, one named (first choices: WorkOS AuthKit) (alternatives: Auth0, Microsoft Entra External ID, Stytch)
- Muse Glimmer 30B: neither first, one named (first choices: Frontegg, LoginRadius) (alternatives: Auth0, Ping Identity)
- Claude Haiku 4.5: neither named (first choices: Descope, Frontegg) (alternatives: OneWelcome Identity Platform, SSOJet, WorkOS)
- GPT-5.4 mini: neither named (first choices: Frontegg) (alternatives: Auth0/Okta Customer Identity Cloud, FusionAuth, Okta)
- Mistral Small: neither named (first choices: LoginRadius) (alternatives: Thales OneWelcome)

## What the models said about Auth0

- "Budget Trap to Avoid: Auth0 (Okta) ... it is not recommended for companies on a limited budget" (Gemini 3.5 Flash, budget prompt, hard negative)
- "The Catch: It can become exceptionally expensive. Because its pricing scales heavily on Monthly Active Users (MAUs), a growing customer base can lead to a highly ballooned bill." (Gemini 3.5 Flash, comparative prompt, soft negative)
- "Auth0 has issued advisories about misconfigurations, account creation fraud, credential attacks, MFA bypass, and session/token hijacking." (GLM 4.7 FlashX, negative prompt, soft negative)
- "Frontegg (if multi-tenant org management is a priority) or Auth0 (if you want the most mature, proven platform) are the strongest overall picks" (DeepSeek V4 Flash, direct prompt, first choice)
- "Medium (Standard Devs) | Fully Managed Cloud<br>Best balance of speed, security, and ease of use. | Auth0 (Okta), AWS Cognito, Firebase Auth" (Qwen 3.7 Flash, scale prompt, first choice)
- "Choose Auth0 if you want to get a product to market quickly and value developer flexibility over on-prem control." (GLM 4.7 FlashX, comparative prompt, first choice)

## What the models said about Clerk

- "Choose Clerk only if you are a startup ... not necessarily the cheapest long-term option" (Perplexity Sonar, budget prompt, soft negative)
- "For most companies with limited budgets, Clerk's free tier or self-hosted Keycloak are the two best choices" (DeepSeek V4 Flash, budget prompt, first choice)
- "Clerk is my pick for a small team that wants to keep costs low without building much authentication infrastructure." (GPT-6 Luna, budget prompt, first choice)
- "Frontegg and Clerk are particularly well-suited due to their B2B-focused features and ease of integration" (Mistral Small, paraphrase prompt, first choice)

Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category. Comparisons are drawn for the top eight products in each category. Published under CC BY 4.0; the output is the models' output, and nothing here is a recommendation by the index.