Base UI provides unstyled React components for building accessible web apps and design systems. It’s aimed at teams that want the structure and interaction patterns of a component library without inheriting a visual style, making it easier to apply a custom design language consistently.

The product is positioned around flexibility and accessibility: you get the foundational building blocks needed for menus, dialogs, forms, and other interface primitives while keeping full control over styling. That makes it a practical fit for product teams and developers creating polished interfaces that need to match an existing brand system.