Quickstart

Get started with Base UI, a library of headless ("unstyled") React UI components and low-level hooks.

Installation

@mui/base is completely standalone – run one of the following commands to add Base UI to your React project:

Peer dependencies

Please note that react and react-dom are peer dependencies too:

"peerDependencies": {
  "react": "^17.0.0 || ^18.0.0",
  "react-dom": "^17.0.0 || ^18.0.0"
},

Implementing a Button

This is a quick tutorial that goes through the basics of using and styling Base UI components by replicating a button from GitHub's UI, using their Primer design system as a reference.

Components and hooks

Base UI provides a <Button /> component and a useButton hook. Both can be used to build a button, and each has its own benefits and trade-offs—see Components vs. hooks for details.

The code snippets below demonstrate the basic implementation of each:

Button component

import * as React from 'react';
import Button from '@mui/base/Button';

export default function App() {
  return <Button>Click Me</Button>;
}

useButton hook

import * as React from 'react';
import useButton from '@mui/base/useButton';

export default function App() {
  const { getRootProps } = useButton();
  return (
    <button type="button" {...getRootProps()}>
      Click Me
    </button>
  );
}

Base UI comes with no styles or styling solution—here's what the Button component looks like out of the box:

You can use any styling method of your choice to make fully customizable components for your app. See Customization for more details on customization strategies.

Here are some styling examples:

Styling with CSS

Pass a className prop and use it as a styling hook:

/* styles.css */

.btn {
  background-color: #1f883d;
  /* the rest of the styles */
}

/* App.js */

<Button className="btn">Create Repository</Button>

Base UI components like the Button come with a classes object (e.g. buttonClasses) that provides class hooks for styling a particular state.

/* To style the disabled state: */

.${buttonClasses.disabled} { /* ".MuiButton-disabled" */
  cursor: not-allowed;
}

The demo below shows how to create the Primer button using plain CSS with Base UI's Button component and useButton hook:

Styling with Tailwind CSS

After installing Tailwind CSS, pass its utility classes to className, as shown below:

<Button className="bg-green-600 rounded-md py-1 px-4...">Create Repository</Button>

The demo below shows how to build the Primer button using Tailwind CSS:

Styling with MUI System

MUI System is a small set of CSS utilties that provide a styled-components-like API for building out designs that adhere to a theme.

MUI System's core utility is a styled function that's equivalent to the styled() function in emotion and styled-components. Interpolations or arguments that are functions called by styled receive the theme from an upper ThemeProvider.

import * as React from 'react';
import { ThemeProvider } from '@emotion/react';
import { styled } from '@mui/system';
import Button from '@mui/base/Button';

const theme = {
  colors: {
    primary: 'green',
  },
};

const GitHubButton = styled(Button)(
  ({ theme }) => `
    background-color: ${theme.colors.primary /* => 'green' */};
  `,
);

render(
  <ThemeProvider theme={theme}>
    <GitHubButton>Create Repository</GitHubButton>
  </ThemeProvider>,
);

Most of the demos in the Base UI docs are styled with MUI System in this way. You can inspect the theme object used on this site in your browser console, or explore the default structure in the Material UI Default theme documentation.

The demos below show how to create the Primer button using MUI System:

Button Component with MUI System

import * as React from 'react';
import Button from '@mui/base/Button';
import { styled } from '@mui/system';

const GitHubButton = styled(Button)(
  ({ theme }) => `
    background-color: ${theme.palette.mode === 'dark' ? '#238636' : '#1f883d'};
    ${/* ... the rest of the styles */}
  `,
);

export default function App() {
  return (
    <GitHubButton>Create Repository</GitHubButton>
  );
}

useButton hook with MUI System

import * as React from 'react';
import useButton from '@mui/base/useButton';
import { styled } from '@mui/system';

const GitHubButton = styled('button')(
  ({ theme }) => `
    background-color: ${theme.palette.mode === 'dark' ? '#238636' : '#1f883d'};
    ${/* ... the rest of the styles */}
  `,
);

export default function App() {
  const { getRootProps } = useButton(/* props*/);

  return (
    <GitHubButton type="button" {...getRootProps()}>
      Create Repository
    </GitHubButton>
  );
}

Using the sx prop

MUI System supports the sx prop, which provides a quick way to apply ad-hoc styles using theme-aware values to any component created with styled.

const GitHubButton = styled(Button)(
  ({ theme }) => `
    background-color: ${theme.palette.mode === 'dark' ? '#238636' : '#1f883d'};
    margin: 0;
  `,
);

export default function App() {
  return (
    <GitHubButton sx={{ m: 2 /* => margin: 16px */ }}>
      Create Repository
    </GitHubButton>
  );
}

The demo below shows how to build the Primer button using MUI System along with the sx prop:

Read the MUI System Usage doc for further details.