User management software is crucial for the success of SaaS businesses, offering features such as authentication, access control, reporting, and analytics to manage every touchpoint of users' journeys. The best user management software tools include WorkOS, Frontegg, Keycloak, Auth0, and Stytch, each with their unique features and pricing models. When choosing a user management software, consider factors such as cost, customization, timeline, support and maintenance, expertise, core functionalities, scalability, integration capabilities, user experience, technical support, community and resources, and the specific needs of your business. WorkOS is particularly suited for enterprise-level applications, while Frontegg and Auth0 are ideal for B2B SaaS apps. Keycloak offers a flexible and cost-effective solution with extensive customization options, while Stytch prioritizes security and fraud detection with its suite of APIs.