Auth0, a popular choice for authentication and user management, is increasingly seen as limited by developers as their needs evolve, particularly in areas like multi-tenancy, cost, and support for modern authentication methods. As a result, many are exploring alternatives such as Descope, Amazon Cognito, Firebase Authentication, Keycloak, and authentik. Descope offers a modern, developer-friendly platform with visual workflows and support for various authentication methods, making it suitable for B2B and B2C SaaS applications. Amazon Cognito integrates well with AWS services, while Firebase Authentication provides a quick setup ideal for mobile and early-stage apps. Keycloak offers an open-source solution with extensive customization options, appealing to enterprises needing self-hosted deployments. Lastly, authentik is favored by teams seeking a lightweight, self-hosted solution with robust protocol support. Choosing the right alternative depends on specific needs related to technology stack, scalability, and desired authentication capabilities.