carbon-components-svelte

June 23, 2026 · View on GitHub

Carbon Components Svelte is a Svelte component library that implements the Carbon Design System, an open source design system by IBM. Ship accessible, consistent, production-ready interfaces.

70+ components: from inputs to data tables
5 built-in themes: two light, three dark
Fully typed TypeScript API: props, events, and slots
WCAG 2.1 AA: keyboard and screen-reader ready

The Carbon Svelte ecosystem also includes:

Carbon Icons Svelte: 2,600+ Carbon icons as Svelte components
Carbon Pictograms Svelte: 1,500+ Carbon pictograms as Svelte components
Carbon Charts Svelte: 25+ charts, powered by d3
Carbon Preprocess Svelte: Collection of Svelte preprocessors for Carbon

Installation

# npm
npm i carbon-components-svelte

# pnpm
pnpm add carbon-components-svelte

# Yarn
yarn add carbon-components-svelte

# Bun
bun add carbon-components-svelte

Usage

Styling

Before importing components, you will need to first apply Carbon component styles. The Carbon Design System supports five themes (2 light, 3 dark).

white.css: Default Carbon theme (light)
g10.css: Gray 10 theme (light)
g80.css: Gray 80 theme (dark)
g90.css: Gray 90 theme (dark)
g100.css: Gray 100 theme (dark)
all.css: All five themes (White, Gray 10, Gray 80, Gray 90, Gray 100) using CSS variables

Each StyleSheet is generated from the flagship carbon-components library.

The compiled CSS is generated from the following .scss files:

Import one theme once at the top-level entry point of your app, like index.js or src/+layout.svelte.

CSS StyleSheet

// White theme
import "carbon-components-svelte/css/white.css";

// Gray 10 theme
import "carbon-components-svelte/css/g10.css";

// Gray 80 theme
import "carbon-components-svelte/css/g80.css";

// Gray 90 theme
import "carbon-components-svelte/css/g90.css";

// Gray 100 theme
import "carbon-components-svelte/css/g100.css";

// All themes
import "carbon-components-svelte/css/all.css";

The most performant method to load styles is to import SCSS directly from carbon-components. Although it requires more set up, you can reduce the size of the bundle CSS by importing individual component styles instead of a pre-compiled CSS StyleSheet.

Refer to the official Carbon guide on SASS for documentation.

Dynamic theming

To switch themes at runtime, import the combined "all.css" StyleSheet instead of a single theme. It bundles all five themes and toggles between them through a theme attribute on the HTML element.

import "carbon-components-svelte/css/all.css";

Update the theme by setting the theme attribute on the html element. The default theme is "white".

<!doctype html>
<html lang="en" theme="g10">
  <body>
    ...
  </body>
</html>

Or programmatically switch between each of the five Carbon themes by setting the theme attribute on the HTML element.

<script>
  let theme = "white"; // "white" | "g10" | "g80" | "g90" | "g100"

  $: document.documentElement.setAttribute("theme", theme);
</script>

Alternatively, use the Theme component to manage the theme reactively.

Importing components

Import components from carbon-components-svelte in the script tag of your Svelte file. Visit the documentation site for examples.

<!-- App.svelte -->
<script>
  import { Accordion, AccordionItem } from "carbon-components-svelte";
</script>

<Accordion>
  <AccordionItem title="Section 1" open> Content 1 </AccordionItem>
  <AccordionItem title="Section 2"> Content 2 </AccordionItem>
  <AccordionItem title="Section 3"> Content 3 </AccordionItem>
</Accordion>

Refer to the documentation site for component API documentation.

Preprocessors & Plugins

carbon-preprocess-svelte is a collection of Svelte preprocessors for Carbon. It trims build times and bundle size with two drop-in tools for faster HMR in development and leaner CSS when you ship.

Note

Using carbon-preprocess-svelte is optional and not a prerequisite for this library. It should be installed as a development dependency.

# npm
npm i -D carbon-preprocess-svelte

# pnpm
pnpm add -D carbon-preprocess-svelte

# Yarn
yarn add -D carbon-preprocess-svelte

# Bun
bun add -D carbon-preprocess-svelte

`optimizeImports`

optimizeImports is a Svelte preprocessor that rewrites barrel imports from Carbon components/icons/pictograms packages to their source Svelte code paths. This can significantly speed up development and production build compile times while preserving typeahead and autocompletion offered by integrated development environments (IDE) like VS Code.

The preprocessor optimizes imports from the following packages:

Before & After

- import { Button } from "carbon-components-svelte";
+ import Button from "carbon-components-svelte/src/Button/Button.svelte";

- import { Add } from "carbon-icons-svelte";
+ import Add from "carbon-icons-svelte/lib/Add.svelte";

- import { Airplane } from "carbon-pictograms-svelte";
+ import Airplane from "carbon-pictograms-svelte/lib/Airplane.svelte";

`optimizeCss`

optimizeCss is a Vite plugin that removes unused Carbon styles at build time, often removing hundreds of kilobytes from production bundles. The plugin is compatible with Rollup (Vite extends the Rollup plugin API).

carbon-components-svelte@0.85.0 or greater is required.

$ vite build

Optimized index-CU4gbKFa.css
- Before: 606.26 kB
+ After:   53.22 kB (-91.22%)

dist/index.html                  0.34 kB │ gzip:  0.24 kB
dist/assets/index-CU4gbKFa.css  53.22 kB │ gzip:  6.91 kB
dist/assets/index-Ceijs3eO.js   53.65 kB │ gzip: 15.88 kB

Note

This is a plugin and not a Svelte preprocessor. It should be added to the list of vite.plugins. For Vite set-ups, this plugin is only run when building the app. For Rollup and Webpack, you should conditionally apply the plugin to only execute when building for production.

Configure your bundler

Add optimizeImports to your Svelte preprocessor and optimizeCss to your bundler plugins. See examples for full configurations.

Vite

// vite.config.js
import { svelte, vitePreprocess } from "@sveltejs/vite-plugin-svelte";
import { optimizeCss, optimizeImports } from "carbon-preprocess-svelte";

export default {
  plugins: [
    svelte({
      preprocess: [vitePreprocess(), optimizeImports()],
    }),
    optimizeCss(),
  ],
};

SvelteKit

// svelte.config.js
import adapter from "@sveltejs/adapter-static";
import { vitePreprocess } from "@sveltejs/vite-plugin-svelte";
import { optimizeImports } from "carbon-preprocess-svelte";

const config = {
  preprocess: [vitePreprocess(), optimizeImports()],
  kit: { adapter: adapter() },
};

export default config;

// vite.config.js
import { sveltekit } from "@sveltejs/kit/vite";
import { optimizeCss } from "carbon-preprocess-svelte";
import { defineConfig } from "vite";

export default defineConfig({
  plugins: [sveltekit(), optimizeCss()],
});

Rollup

// rollup.config.js
import svelte from "rollup-plugin-svelte";
import { optimizeCss, optimizeImports } from "carbon-preprocess-svelte";

const production = !process.env.ROLLUP_WATCH;

export default {
  plugins: [
    svelte({
      preprocess: [optimizeImports()],
    }),
    production && optimizeCss(),
  ],
};

Webpack

// webpack.config.mjs
import { OptimizeCssPlugin, optimizeImports } from "carbon-preprocess-svelte";

export default {
  module: {
    rules: [
      {
        test: /\.svelte$/,
        use: {
          loader: "svelte-loader",
          options: {
            preprocess: [optimizeImports()],
          },
        },
      },
    ],
  },
  plugins: [new OptimizeCssPlugin()],
};

Icons and pictograms

The icon and pictogram sets ship as separate packages of individual Svelte components. Each is optional, so install only what you need.

Icons

2,600+ icons designed for product UI, in four sizes (16, 20, 24, and 32 pixels), set with a single prop.

# npm
npm i carbon-icons-svelte

# pnpm
pnpm add carbon-icons-svelte

# Yarn
yarn add carbon-icons-svelte

# Bun
bun add carbon-icons-svelte

<script>
  import Add from "carbon-icons-svelte/lib/Add.svelte";
</script>

<Add size={24} />

Pictograms

1,500+ illustrative pictograms for empty states, onboarding, hero sections, and feature callouts. Larger than icons, 64px by default.

# npm
npm i carbon-pictograms-svelte

# pnpm
pnpm add carbon-pictograms-svelte

# Yarn
yarn add carbon-pictograms-svelte

# Bun
bun add carbon-pictograms-svelte

<script>
  import Cloud from "carbon-pictograms-svelte/lib/Cloud.svelte";
</script>

<Cloud />

Documentation for LLMs

Documentation is available in LLM-friendly plain text for use with coding assistants, plus a standalone Markdown document for every component. Append .md to any component's URL to read it.

llms.txt: a component index where each entry links to its per-component Markdown doc, sized for model context windows.
llms-full.txt: the full component documentation in a single plain-text file.

This package uses IBM Telemetry to collect de-identified and anonymized metrics data in CI environments. By installing this package as a dependency you are agreeing to telemetry collection. To opt out, see Opting out of IBM Telemetry data collection. For more information on the data being collected, please see the IBM Telemetry documentation.

carbon-components-svelte

Documentation

Installation

Usage

Styling

CSS StyleSheet

SCSS

Dynamic theming

Importing components

Preprocessors & Plugins

`optimizeImports`

`optimizeCss`

Configure your bundler

Icons and pictograms

Icons

Pictograms

Documentation for LLMs

Examples

TypeScript support

Contributing

Changelog

License

IBM Telemetry