Radix UI
Free MIT
Open-source, accessible component library for building high-quality, design-system-ready React UIs.
Overview
Radix UI provides two complementary tools: Radix Primitives — unstyled, WAI-ARIA compliant headless React components for building custom design systems — and Radix Themes — a fully styled, ready-to-use React component library with a polished design system built on the primitives. Both are open-source, maintained by WorkOS, and power the internals of shadcn/ui and hundreds of design systems.
Best Suited For
"Design system engineers and teams building custom, branded UI kits who want a rock-solid accessible component foundation."
Advantages
- Industry-leading accessibility — every component is WAI-ARIA compliant with full keyboard navigation and screen reader support.
- Unstyled primitives give teams full design control; pair with any CSS solution including Tailwind, CSS Modules, or styled-components.
- Maintained by WorkOS and powers major ecosystems including shadcn/ui, making it the most trusted headless React primitive library.
Limitations
- Primitives are unstyled — teams must implement their own visual design on top.
- Not a polished out-of-the-box design system; works best as a foundation for a custom one.
