Headless UI is an open-source component library that provides fully accessible, unstyled UI primitives for building modern web interfaces. Developed by the creators of Tailwind CSS, it is designed for React and Vue applications and focuses on separating logic and accessibility from visual styling.

Unlike traditional UI libraries that ship with predefined styles, Headless UI provides only the behavioral logic and accessibility features (such as keyboard navigation and ARIA compliance), leaving developers free to design and style components however they want.

The library includes common interactive components such as dropdown menus, modals, dialogs, switches, tabs, and popovers. These components are implemented as composable primitives that developers can integrate into their applications and style using Tailwind CSS or any other styling system.

Headless UI solves the problem of rigid, opinionated UI frameworks by giving developers complete control over markup and styling while still providing production-ready accessibility and behavior. This makes it particularly useful for teams building custom design systems or highly branded interfaces.

It is widely used in modern frontend development, especially in projects that rely on Tailwind CSS, React, or Vue, and is part of a broader ecosystem of tools from Tailwind Labs.

Key features include:

• Unstyled UI components with full design flexibility
• Built-in accessibility (ARIA, keyboard navigation, focus management)
• Support for React and Vue frameworks
• Composable primitives for building custom components
• Seamless integration with Tailwind CSS and custom styling systems

Common use cases include:

• Building custom design systems
• Creating accessible UI components
• Developing React or Vue applications
• Prototyping interfaces
• Implementing interactive elements like modals, menus, and tabs

Headless UI is developed by Tailwind Labs, the team behind Tailwind CSS, and is maintained as an open-source project.