Fluent UI is a collection of utilities, React components, and web components for building web applications that follow Microsoft's design system.
The project addresses the need for consistent, accessible UI components across web platforms by providing three distinct implementations. Fluent UI React v9 represents the forward-looking approach with modern architecture, while v8 offers a mature, production-tested alternative. Web Components provide a framework-agnostic implementation. The repository supports gradual migration between versions, allowing teams to adopt v9 incrementally alongside existing v8 or v0 components rather than requiring a complete rewrite.
Teams should choose Fluent UI if they are building applications that need to align with Microsoft's design language or if they require components used in Microsoft 365, Office, or Edge. The v9 release is the recommended path for new projects, while v8 remains suitable for teams with established codebases. The web components option serves projects that need to work across different JavaScript frameworks or prefer framework-agnostic solutions. Each implementation has separate documentation, changelogs, and npm packages, making it clear which version suits a particular use case.
The project maintains active development across all three tracks with organized issue tracking for each implementation. The repository provides comprehensive documentation and quick-start guides tailored to each variant, reflecting ongoing investment in developer experience. The separation of concerns between v9, v8, and web components suggests deliberate maintenance of multiple maturity levels to serve different adoption scenarios.
