Top Open-Source Auth0 Alternatives in 2026: Secure & Self-Hosted Options

Managing authentication at scale is rarely simple. SaaS teams must balance security, user experience, compliance, and operational efficiency, all while supporting standards like OAuth, OIDC, and SAML. 

For many teams, Auth0 has provided a quick way to get started - but it may not remain the best fit as requirements evolve.

As user bases grow and enterprise customers demand greater control over data and identity workflows, open-source and self-hosted identity solutions become increasingly attractive. These platforms offer flexibility, transparency, and long-term cost predictability.

In this blog, we examine the top open-source Auth0 alternatives in 2026 and explain when and why each option makes sense. 

Why Consider Auth0 Alternatives?

While Auth0 simplifies authentication, it does not always fit every organization’s long-term needs. Several factors push SaaS teams to consider alternatives:

Cost at Scale

Auth0 pricing is tied to monthly active users (MAUs) and premium feature tiers. For SaaS platforms with large user bases, costs can increase rapidly and become unpredictable.

Data Ownership and Infrastructure Control

Certain industries require full control over where identity data is stored and processed. Open-source solutions allow self-hosting, giving organizations control over data residency and infrastructure compliance.

Customization and Extensibility

While Auth0 supports rules and actions for customizing authentication flows, deep changes to workflows, provisioning, or data models may be limited. Open-source alternatives often allow complete flexibility to tailor the identity system to your needs.

Vendor Lock-In

Heavy reliance on proprietary features or workflows can make migrations difficult. Open-source solutions reduce dependency on a single vendor, providing long-term flexibility.

Compliance and Security Requirements

Some organizations have strict compliance requirements, such as GDPR, SOC2, or HIPAA. Open-source platforms allow teams to implement and audit policies directly, ensuring compliance without relying on external vendors.

By considering these factors, SaaS teams can identify identity solutions that fit both operational and strategic goals.

Key Considerations for Open-Source Auth0 Alternatives

When evaluating an open-source identity platform, several criteria are essential:

1. Standards and Protocol Support

A robust identity solution should support:

• OAuth 2.0 for authorization
• OpenID Connect (OIDC) for authentication
• SAML 2.0 for enterprise SSO

Standards compliance ensures seamless integration with enterprise directories, SaaS applications, and internal systems.

2. Deployment Flexibility

Open-source platforms should support multiple deployment models:

• Self-hosted on-premise
• Private cloud deployments
• Containerized setups with Docker or Kubernetes

Flexible deployment is critical for organizations with regulatory or network isolation requirements.

3. Extensibility and Customization

Teams should be able to:

• Customize login, registration, and multi-factor authentication flows
• Extend user attributes and roles
• Integrate with internal systems and APIs
• Implement fine-grained access policies

4. Enterprise Readiness

For production use, platforms should offer:

• High availability and scalability
• Logging, audit trails, and monitoring
• Role-based and attribute-based access control
• Multi-tenant support
• Active community and documentation

These features ensure identity systems can support complex SaaS products and enterprise customers.

Top Open-Source Auth0 Alternatives

Many SaaS teams are turning to open-source identity platforms to reduce vendor lock-in, control costs, and meet enterprise compliance requirements. The following Auth0 alternatives offer standards-based authentication, and flexible deployment models. 

1. Authgear

Authgear is a modern, open-source identity platform designed for frontline, external, and customer users. It enables SaaS teams and enterprises to secure large, non-corporate user bases without extending traditional workforce IAM such as AD, Entra ID, or Okta.

Key Capabilities

• OAuth 2.0, OpenID Connect (OIDC), and SAML
• Passwordless authentication with passkeys (WebAuthn)
• WhatsApp OTP, SMS, and email-based login
• Built-in MFA, account lockout, bot detection, and rate limiting
• Separation of corporate and external identities
• Self-hosted or managed deployment options

Strengths

Authgear delivers low-friction authentication with security enforced by default. Users log in using familiar methods like phone numbers or personal email, while teams centralize access policies, auditing, and protection across applications. It scales cost-effectively for large frontline and external user populations.

Best Use Cases

• Frontline staff, partners, contractors, and customer-facing apps
• SaaS platforms requiring secure, fast login at scale
• Organizations avoiding corporate IAM sprawl and unpredictable MAU costs

2. Keycloak

Keycloak is one of the most mature open-source identity and access management platforms. Developed by Red Hat, it is widely used in enterprise environments.

Key Features

• OAuth 2.0, OpenID Connect, and SAML support
  
• Built-in admin console
  
• Role-based access control (RBAC)
  
• Identity brokering and social login
  
• Multi-tenant support through realms
  
• LDAP and Active Directory integration
  

Strengths

Keycloak is feature-rich and supports complex enterprise identity scenarios. It integrates well with existing directories and provides strong administrative controls.

Considerations

• Requires infrastructure management
  
• Customization often requires Java knowledge
  
• User interface is functional but not modern
  

Best Use Cases

Large SaaS platforms with dedicated infrastructure teams, complex user hierarchies, and enterprise-level identity requirements.

3. Authentik

Authentik is a modern, policy-driven open-source identity provider. It emphasizes usability and flexibility, allowing teams to customize authentication workflows visually.

Key Features

• OAuth 2.0, OIDC, and SAML support
• Visual authentication flow builder
• Multi-factor authentication
• Kubernetes-friendly deployment
  

Strengths

Authentik’s flow-based approach makes authentication customization accessible without deep technical expertise. It is designed for modern SaaS architectures and cloud-native deployments.

Considerations

• Smaller ecosystem compared to Keycloak
  
• Fewer enterprise case studies
  

Best Use Cases

SaaS teams that require modern authentication flows and self-hosting support for enterprise clients.

4. ORY

ORY is an API-first open-source identity platform built for microservice architectures. It provides modular components that can be combined for full identity and access management.

Key Components

• ORY Kratos: Identity management
  
• ORY Hydra: OAuth 2.0 and OIDC server
  
• ORY Keto: Authorization and permission management
  
• ORY Oathkeeper: Identity-aware proxy
  
  

Strengths

ORY is highly flexible and suitable for teams building custom authentication systems. Its API-first design integrates seamlessly into headless applications and microservices.

Considerations

• Steeper learning curve
  
• Requires managing multiple services
  
• Limited built-in UI
  

Best Use Cases

Engineering-driven SaaS teams with API-first architecture and complex authorization needs.

5. ZITADEL

ZITADEL is a modern IAM platform designed for scalability, security, and compliance. It supports both self-hosted and managed deployment models.

Key Features

• OAuth 2.0, OIDC, and SAML
  
• Event-driven identity changes
  
• Multi-tenant architecture
  
• Fine-grained access control
  
• Audit logging and compliance support
  

Strengths

ZITADEL provides enterprise-grade security and compliance features while remaining modern and cloud-native. It supports large-scale SaaS deployments with complex user structures.

Considerations

• Smaller community than Keycloak
  
• Ecosystem still growing

Best Use Cases

SaaS platforms that need scalable, compliant, and secure identity management with enterprise features.

Open-Source vs Managed Identity Platforms

As SaaS platforms grow, identity infrastructure decisions become more strategic. Comparing open-source and managed identity platforms highlights key differences in ownership, flexibility, and operational overhead.

Benefits of Open-Source Identity

• Full control over data and infrastructure
• Predictable costs without MAU pricing
• Complete customization of flows and attributes
• Reduced vendor lock-in

Challenges

• Infrastructure and operational responsibility
• Monitoring, scaling, and high availability planning
• Security patch management
• Requires internal expertise

Many organizations adopt a hybrid approach, starting with managed services and transitioning to open-source solutions as they scale or require more control.

Choosing the Right Open-Source Auth0 Alternative

There is no one-size-fits-all solution. Teams can consider:

• Keycloak: Full-featured enterprise IAM, suitable for complex SaaS deployments
• Authentik: Flexible, visual authentication flows for modern SaaS applications
• ORY: API-first, modular IAM for microservices and headless architectures
• ZITADEL: Scalable and compliant identity platform with enterprise security features

Selection should factor in standards support, SSO needs, operational overhead, and long-term scalability.

Migration Considerations: Moving Away from Auth0

Migrating from Auth0 to an open-source identity platform is a strategic decision that requires careful planning. 

While most modern identity providers support standard protocols, the migration effort depends on how deeply Auth0-specific features are embedded in your application.

Identity Data and User Accounts

The first step in migration is exporting user data, including profiles, credentials, and metadata. Most open-source platforms allow importing users, but teams should review differences in user schemas, password hashing algorithms, and attribute handling. In some cases, users may need to reset passwords during the transition.

Authentication Flows and Custom Logic

Auth0 rules, actions, and custom scripts often contain business logic tied to authentication or authorization. These flows must be reimplemented using the new platform’s customization mechanisms, such as policies, hooks, or flow builders. Open-source platforms typically provide more flexibility, but require upfront effort to replicate existing behavior.

Applications and Client Configuration

Each application integrated with Auth0, web apps, mobile apps, APIs, and third-party services, must be reconfigured to point to the new identity provider. This includes updating client IDs, secrets, redirect URIs, and token validation logic.

Enterprise Integrations

For SaaS platforms serving enterprise customers, special attention is needed for SAML connections, and SSO configurations. Testing enterprise identity flows in parallel environments helps ensure a smooth transition without disrupting customer access.

Gradual Migration Strategy

Many teams adopt a phased approach:

• New users authenticate through the new identity provider
• Existing users are migrated in batches
• Auth0 remains active during a transition period

This approach minimizes risk and allows teams to validate stability before fully decommissioning Auth0.

Operational Readiness

Before completing the migration, teams should ensure:

• Monitoring and alerting are in place
• Backup and recovery procedures are defined
• Security patches and upgrades are part of regular operations

A well-planned migration reduces downtime, avoids user friction, and ensures the long-term success of a self-hosted identity system.

Bottom Line

Open-source Auth0 alternatives in 2026 are mature, secure, and well-suited for modern SaaS platforms. They offer greater control over identity data, flexible deployment options, and long-term cost predictability without sacrificing standards compliance or enterprise features.

Authgear stands out as a modern, Auth0-like solution built for SaaS teams that want flexibility without added complexity. With native support for OAuth, OIDC, SAML, and MFA, Authgear simplifies enterprise SSO, automates user provisioning, and supports secure scaling.

Explore Authgear today to streamline identity management and ensure consistent, secure access across all your applications.

FAQs

Are open-source Auth0 alternatives secure?

Yes, when configured and maintained correctly. Many are used in enterprise production environments.

Do these platforms support SSO? 

Most support OpenID Connect and SAML for single sign-on.

Can I migrate from Auth0 later?

Yes, but the complexity depends on how deeply proprietary features are used.

Do open-source alternatives support multi-factor authentication (MFA)?

Most modern open-source identity providers, including Authgear, Keycloak, and Authentik, support MFA. Teams can implement passwordless login, SMS/OTP, authenticator apps, and WebAuthn passkeys depending on platform capabilities and compliance requirements.