Keycloak vs Authentik - Open Source SSO for Business

How many passwords do your employees use every day? Email, CRM, HR systems, cloud panels, project tools - in an average company that's a dozen separate logins. Each one is a potential security gap, a forgotten password and another ticket to the IT department. Single sign-on (SSO) solves this problem - and thanks to the open-source systems Keycloak and Authentik, you can run it in-house, without paying a subscription for every user.

What is SSO (Single Sign-On)?

Single Sign-On is a mechanism that lets a user log in once and then access all connected applications without re-entering credentials. Instead of remembering a dozen passwords, an employee uses a single, strong account - additionally secured with multi-factor authentication (MFA).

Behind the scenes, SSO relies on an Identity Provider (IdP) that centrally manages accounts and confirms the user's identity to individual applications using open standards: OIDC (OAuth 2.0), SAML 2.0 and LDAP.

The key benefit: one account, one place to manage access, one point to enforce security policies.

Why implement SSO in your company?

1. A real security boost

Centralized identity management means you enforce MFA, password policies and lockouts in one place - for all applications at once. When an employee leaves, you deactivate a single account and instantly revoke access to every system.

2. The end of password chaos

Fewer passwords means fewer sticky notes under keyboards, fewer reused combinations and fewer "I forgot my password" tickets. That's a measurable time saving for IT and a real reduction of the attack surface.

3. Independence and predictable costs

Commercial SSO solutions (e.g. Okta, Microsoft Entra ID) charge per user, per month. With dozens or hundreds of accounts, that's a significant, growing cost. Keycloak and Authentik are free and open source - you pay only for infrastructure and deployment.

4. Data sovereignty

Your employees' authentication data stays on your server or in a chosen EU data center. This is crucial for GDPR compliance and for industries handling sensitive data.

Keycloak - the enterprise standard

Keycloak is a mature identity management system developed with the backing of Red Hat and written in Java. For years it has been the de facto standard in large, complex environments.

Strengths:

• Very broad protocol support: OIDC, OAuth 2.0, SAML 2.0,
• Advanced LDAP and Active Directory federation,
• Fine-grained authorization and role management,
• Proven at massive scale,
• A huge community and rich documentation.

Worth knowing: Keycloak is more resource-intensive (typically 1.5-4 GB RAM) and has a steeper learning curve - it's a tool for large deployments.

Authentik - modern and simple

Authentik is a newer system written in Python, designed for usability and modern self-hosted stacks. It's gaining huge popularity among SMBs and DevOps teams.

Strengths:

• A clean, modern UI and a visual login flow designer,
• Low resource usage (around 600 MB RAM idle),
• Fast deployment and easy configuration,
• Support for OIDC, SAML, LDAP, SCIM and MFA,
• A unique "outpost" system - secures applications without native SSO support via a reverse proxy, with no changes to the application code.

Worth knowing: Authentik is younger but very actively developed - it excels in modern, cloud-native environments.

Keycloak vs Authentik - comparison

Which solution to choose?

There's no single right answer - the choice depends on the scale and nature of your organization:

• Choose Keycloak if you need advanced Active Directory/LDAP federation, very broad SAML protocol support and fine-grained authorization policies in a large, complex environment.
• Choose Authentik if you value fast deployment, a modern interface, low resource usage and easy protection of applications that lack native SSO.

In practice, for most small and medium businesses Authentik will be the faster, more convenient path to SSO, while Keycloak remains the natural choice where integration with extensive corporate infrastructure matters most.

Who is open-source SSO for?

Deploying Keycloak or Authentik works especially well for:

• companies with many applications (cloud and on-premise) where employees juggle multiple logins,
• security-conscious organizations that want to enforce MFA and centralized access policies,
• companies wanting to avoid per-user subscriptions in commercial SSO systems,
• regulated industries (healthcare, legal, finance) where the sovereignty of authentication data is a priority.

How will nex-IT deploy SSO in your company?

We handle the full technical deployment and maintenance of SSO systems:

• Needs analysis - choosing Keycloak or Authentik for your environment and applications,
• Installation and configuration - an identity provider on your server or in an EU data center,
• Application integration - connecting email, CRM, panels and tools via OIDC, SAML or LDAP,
• Active Directory/LDAP federation - if you already use a company domain,
• MFA and policy configuration - multi-factor authentication and access rules,
• Backup, monitoring and maintenance - continuous oversight of availability.

Summary

Single sign-on is one of the most effective ways to simultaneously increase security and convenience in a company. Thanks to the open-source Keycloak and Authentik, you can deploy professional SSO without per-user subscriptions and with full control over your authentication data. Keycloak is the choice for large enterprise environments, Authentik - for companies that value modernity and fast deployment.

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Considering SSO for your company? We'll help you choose between Keycloak and Authentik and handle the entire deployment - from installation, through application integration, to maintenance. Contact us!