WorkOS

WorkOS builds APIs that let software developers add enterprise authentication, user management, permissions and audit logs to applications. AuthKit supplies authentication UI, while Single Sign-On connects applications to SAML and OIDC identity providers. Directory Sync handles employee account provisioning through enterprise directories and HR systems; the hosted Admin Portal lets customers’ IT administrators configure connections themselves. Beyond developer infrastructure, Atlas gives teams a Slack application for answering questions and automating tasks with customizable AI agents, persistent memory and scoped integrations.

Founder and CEO Michael Grinich started WorkOS in 2019 after his experience at Nylas Mail exposed how missing enterprise requirements could block an otherwise popular product’s business. WorkOS launched publicly in 2020. Its technical approach normalizes enterprise integrations behind a common API, reducing the number of separate systems developers must integrate. In 2022, WorkOS acquired Modulz, the creator of Radix, whose unstyled, accessible UI components help developers build their own design systems.

In 2026, the company reported thousands of customers and billions of API requests each month, naming OpenAI, Anthropic, Cursor and Perplexity among its users. That year, WorkOS raised $100 million in Series C financing at a $2 billion valuation, with Meritech and Sapphire leading the round.