Base UI

Base UI is a library of unstyled, accessible React components built by the MUI team, the people behind Material UI. Unlike pre-styled component libraries that impose visual opinions, Base UI takes a headless approach: it provides all the functionality and behavior without any CSS. This gives developers complete control over the look and feel of their UI while avoiding the common struggle of overriding opinionated default styles.

Every Base UI component is built with accessibility as a first-class concern. The library follows WAI-ARIA guidelines and ensures proper keyboard navigation, focus management, and screen reader support out of the box. Components include buttons, menus, dialogs, tabs, sliders, select dropdowns, and form controls. Because there is zero styling included, developers can bring any CSS approach they prefer — Tailwind CSS, CSS Modules, styled-components, or plain CSS — and build a design system that is truly their own.

Previously known as MUI Base (@mui/base), the project is now standalone under the Base UI name. Full documentation and getting-started guides are available at base-ui.com, and the source code is open on GitHub.