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Customer identity and access management · November 2026 Edition

FusionAuth vs Keycloak

Zero of fourteen models named FusionAuth first on the direct prompt; zero named Keycloak. FusionAuth was named by eight of the fourteen models and Keycloak by ten and FusionAuth carries 14 labels and Keycloak 15, so the shares are not directly comparable.

FusionAuth

accepted challenger

Named in two categories this edition.

Keycloak

accepted challenger

Named in five categories this edition.

First-choice share6%4%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.
Negative rate0%20%Negative labels as a share of the product's labels, 0 to 100.
Rank in category#5#7A position in a field of 16; printed, not drawn.
Labels1415A count; the two differ.
The two percentage rows are drawn on one 0 to 100 track, FusionAuth reading right to left. Rank and label count are printed, not drawn.Frontegg was named alongside these two in twelve of the fourteen direct answers. Auth0 vs FusionAuth · Auth0 vs Keycloak · WorkOS AuthKit vs FusionAuth

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; every quote names the model and the prompt it came from. Both figures come from the customer identity and access management page.

By framing

How many of the fourteen models made each the first choice, per way of asking, and how many argued against it.
FusionAuthFirst choices, of fourteen modelsKeycloak
Direct00
Paraphrase00
Comparative001 against Keycloak
Budget-constrained32
Scale-constrained00
Negative002 against Keycloak
Bars are first choices, 0 to 14 each sideModels that argued againstA model can name both, so the two sides of a row do not sum to fourteen.

Across every category in the November 2026 Edition, FusionAuth and Keycloak were named in the same answer eighteen times, of the 52 answers naming FusionAuth and the 63 naming Keycloak. In those answers Keycloak took the first choice zero times and FusionAuth two.

Every model, every framing

The eighty-four answers behind the chart above, one cell each: where FusionAuth and Keycloak stood in it.
ModelDirectParaphraseComparativeBudget-constrainedScale-constrainedNegative
Claude Haiku 4.5
GPT-5.4 mini
Gemini 3.5 Flash
Perplexity Sonar
Grok 4.20
Mistral Small
DeepSeek V4 Flash
Llama 4 Maverick
Qwen 3.7 Flash
Kimi K2
GLM 4.7 FlashX
MiniMax M2.5
GPT-6 Luna
Muse Glimmer 30B
FusionAuth Keycloak first choice named as an alternative argued againstblank: not namedEach cell is one answer, FusionAuth on the left and Keycloak on the right.

The direct prompt

The plain question, one answer per model, grouped by where FusionAuth and Keycloak stood in it.

Neither was the first choice, one was named

1 of 14 modelsThe answer put something else first and named one of the two as an alternative.
Perplexity SonarAuth0 alternatives: Amazon Cognito, Frontegg, FusionAuth, Microsoft Entra External ID, WorkOS AuthKit

Neither was named

13 of 14 modelsThe answer made no first choice from these two in this category.
Claude Haiku 4.5Auth0 alternatives: Frontegg, OneLogin, The OneWelcome Identity Platform
GPT-5.4 miniAuth0 alternatives: Frontegg, Ping Identity
Gemini 3.5 FlashWorkOS AuthKit alternatives: Clerk, Descope, Frontegg, Stytch
Grok 4.20WorkOS AuthKit alternatives: Auth0, Frontegg, Stytch
Mistral SmallAuth0 alternatives: Frontegg, Microsoft Entra External ID
DeepSeek V4 FlashFrontegg alternatives: Descope, Kinde, WorkOS AuthKit
Llama 4 MaverickAuth0 alternatives: IBM Verify, Microsoft Entra External ID, Ping Identity, WSO2 Identity Server, WorkOS AuthKit
Qwen 3.7 FlashFrontegg alternatives: Auth0, Descope, Microsoft Entra External ID, Stytch
Kimi K2WorkOS AuthKit alternatives: Frontegg, Stytch
GLM 4.7 FlashXAuth0 alternatives: Amazon Cognito, Descope, Frontegg, Microsoft Entra External ID, Ping Identity, SSOJet, Stytch, Transmit Security
MiniMax M2.5OneLogin alternatives: Frontegg, LoginRadius, SSOJet
GPT-6 LunaWorkOS AuthKit alternatives: Auth0, Stytch
Muse Glimmer 30BKinde, WorkOS AuthKit alternatives: Auth0, Frontegg, Okta, OneLogin

Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.

By buyer segment

The same question asked on behalf of a different buyer. Each standing is computed within its segment and they are never added together. The figures above are the mid-market standing, which is the one the category orders by.
Small business
FusionAuth leads by three points.
FusionAuth3%#7 of 15
Keycloak0%#14 of 15
The full small business standing →
Mid-marketThe figures above
FusionAuth leads by two points.
FusionAuth6%#5 of 16
Keycloak4%#7 of 16
The full mid-market standing →
Enterprise
FusionAuth leads by eleven points.
FusionAuth11%#– of 13
Keycloak0%#– of 13
The full enterprise standing →

What the models said about FusionAuth

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Three of four in this category shown.

“For the most budget-conscious approach, FusionAuth and Keycloak stand out because they offer free self-hosted options with no per-user fees.” Claude Haiku 4.5 · budget prompt · first choice
“For most companies with a limited budget, I'd recommend starting with FusionAuth's free Community Edition” DeepSeek V4 Flash · budget prompt · first choice
“Best balance of cost + features: FusionAuth” GPT-5.4 mini · budget prompt · first choice

What the models said about Keycloak

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Four of four in this category shown.

“High Operational Burden: Open-source platforms like Keycloak are feature-complete... you assume 100% of the responsibility for hosting” Gemini 3.5 Flash · negative prompt · soft negative
“Even popular tools like Keycloak (which has seen rising popularity) require significant engineering effort to maintain.” Qwen 3.7 Flash · negative prompt · soft negative
“FusionAuth and Keycloak stand out because they offer free self-hosted options with no per-user fees” Claude Haiku 4.5 · budget prompt · first choice
“Lowest cash spend, higher engineering effort: Keycloak” GPT-5.4 mini · budget prompt · first choice
Also compared

Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.