Using Base UI With Material UI

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Always have enough context from the Base UI documentation to build the component requested by the user.

Base UI as the foundation

Render Base UI components as a foundation for the UI and then pass render prop using proper Material UI components.

For example, a Navigation Menu, should use Link from Material UI as the render element for NavigationMenu.Link.:

import { NavigationMenu } from "@base-ui-components/react/navigation-menu";
import Box from "@mui/material/Box";
import Link from "@mui/material/Link";
import Typography from "@mui/material/Typography";

function MenuLink({
  icon,
  title,
  description,
  ...props
}: NavigationMenu.Link.Props & {
  icon?: React.ReactNode;
  title: string;
  description: string;
}) {
  return (
    <NavigationMenu.Link
      href="#"
      {...props}
      render={
        <Link
          underline="none"
          sx={{
            display: "flex",
            gap: 1,
            p: 1.5,
            borderRadius: 0.5,
            cursor: "pointer",
            transition: "background-color 0.2s",
            "@media (hover: hover)": {
              "&:hover": {
                bgcolor: "action.hover",
              },
            },
          }}
        />
      }
    >
      <Box sx={{ color: "primary.main", display: "flex", mt: 0.25 }}>
        {icon}
      </Box>
      <Box>
        <Typography variant="subtitle2" sx={{ fontWeight: 600, mb: 0.25 }}>
          {title}
        </Typography>
        <Typography
          variant="body2"
          sx={{ color: "text.secondary", lineHeight: 1.4 }}
        >
          {description}
        </Typography>
      </Box>
    </NavigationMenu.Link>
  );
}

For full example, see nav-menu-01.tsx

Another example, using Button from Material UI as the render element for Base UI Trigger component:

import { Menu } from "@base-ui-components/react/menu";
import Button from "@mui/material/Button";

<Menu.Trigger render={<Button />}>File</Menu.Trigger>;

Styling

To style Base UI components, use <Box /> as a render element and pass sx prop to it. Always keep in mind that the sx values should be minimum since Material UI components already have default styling.

import { NavigationMenu } from "@base-ui-components/react/navigation-menu";
import Box from "@mui/material/Box";

<NavigationMenu.List
  render={
    <Box
      component="ul"
      sx={{
        display: "flex",
        justifyContent: "center",
        gap: 2,
        listStyle: "none",
        "& .MuiButton-root[data-popup-open]": {
          bgcolor: "action.selected",
        },
      }}
    />
  }
></NavigationMenu.List>;

Primitive/Non-interactive Components

For non-interactive Base UI components like Meter, Progress, Slider (read-only), etc. that don't have direct semantic Material UI equivalents, always use the render prop pattern with Box.

CRITICAL: Never use component={BaseUIComponent} - this is incorrect and causes issues. Always use Base UI components as the foundation with the render prop.

✅ Correct Pattern

import { Meter } from "@base-ui-components/react/meter";
import Box from "@mui/material/Box";

<Meter.Track
  render={
    <Box
      sx={{
        height: 8,
        width: "100%",
        bgcolor: "action.disabledBackground",
        borderRadius: 1,
        overflow: "hidden",
        position: "relative",
      }}
    />
  }
>
  <Meter.Indicator
    render={
      <Box
        sx={{
          height: "100%",
          bgcolor: "text.primary",
          transition: "width 0.3s ease",
        }}
      />
    }
  />
</Meter.Track>;

❌ Incorrect Pattern

// ❌ NEVER do this - Base UI should be the foundation, not MUI Box
<Box component={Meter.Track} sx={{ ... }}>
  <Box component={Meter.Indicator} sx={{ ... }} />
</Box>

// ❌ NEVER do this - Using asChild prop (not a React pattern)
<Meter.Track asChild>
  <Box sx={{ ... }}>
    <Meter.Indicator asChild>
      <Box sx={{ ... }} />
    </Meter.Indicator>
  </Box>
</Meter.Track>

Key Points

1. Base UI First: Always render Base UI components as the outer wrapper
2. render Prop: Use render={<Box sx={{ ... }} />} to apply Material UI styling
3. Theme Tokens: Use MUI theme tokens in sx prop (e.g., bgcolor: "action.hover", color: "text.primary")
4. Minimal Styling: Keep sx props minimal - only add what's necessary for the design

Reduce duplication

If the same styles are used multiple times for the same Base UI components, create wrapper components to reduce duplication.

import { NavigationMenu } from "@base-ui-components/react/navigation-menu";

function Content(props: BoxProps) {
  return (
    <Box
      sx={{
        padding: 1,
        width: "calc(100vw - 40px)",
        height: "100%",
        "@media (min-width: 500px)": {
          width: "max-content",
          minWidth: "400px",
        },
      }}
      {...props}
    />
  );
}

<NavigationMenu.List>
  <NavigationMenu.Item>
    <NavigationMenu.Content render={<Content />}></NavigationMenu.Content>
  </NavigationMenu.Item>
  <NavigationMenu.Item>
    <NavigationMenu.Content render={<Content />}></NavigationMenu.Content>
  </NavigationMenu.Item>
  <NavigationMenu.Item>
    <NavigationMenu.Content render={<Content />}></NavigationMenu.Content>
  </NavigationMenu.Item>
</NavigationMenu.List>;

TypeScript Props Interface

CRITICAL: When creating wrapper components around Base UI primitives, NEVER duplicate props that are already provided by the Base UI component.

❌ Incorrect - Duplicating Base UI Props

import { PreviewCard } from "@base-ui-components/react/preview-card";

// ❌ BAD: Manually duplicating delay, closeDelay, defaultOpen, etc.
export interface CardPreview01Props {
  trigger: React.ReactNode;
  href: string;
  delay?: number; // Already in PreviewCard.Root.Props
  closeDelay?: number; // Already in PreviewCard.Root.Props
  defaultOpen?: boolean; // Already in PreviewCard.Root.Props
  open?: boolean; // Already in PreviewCard.Root.Props
  onOpenChange?: (open: boolean) => void; // Already in PreviewCard.Root.Props
}

✅ Correct - Extending Base UI Props

import { PreviewCard } from "@base-ui-components/react/preview-card";

// ✅ GOOD: Extend the Base UI component props
export interface CardPreview01Props extends PreviewCard.Root.Props {
  trigger: React.ReactNode;
  href: string;
  imageSrc: string;
  imageAlt: string;
  heading: string;
  description: string;
}

export function CardPreview01({
  trigger,
  href,
  imageSrc,
  imageAlt,
  heading,
  description,
  ...props // This spreads all Base UI props (delay, closeDelay, defaultOpen, etc.)
}: CardPreview01Props) {
  return (
    <PreviewCard.Root {...props}>{/* component content */}</PreviewCard.Root>
  );
}

Key Benefits

1. Type Safety: Automatically get all Base UI prop types without manual maintenance
2. Future-Proof: New Base UI props automatically available in your component
3. No Duplication: Single source of truth for prop definitions
4. Better DX: TypeScript autocomplete shows all available props

When to Define Custom Props

Only define props that are:

• Specific to your wrapper component (like imageSrc, heading)
• Not part of the underlying Base UI component
• Required for your custom implementation logic