> **Warning**
>
> ## THIS IS AN AUTOGENERATED FILE. DO NOT EDIT.
>
> ## Please edit the corresponding file in [/packages/mermaid/src/docs/config/icons.md](../../packages/mermaid/src/docs/config/icons.md).

# Icon Pack Configuration

Mermaid supports icons through Iconify-compatible icon packs. You can register icon packs either **declaratively via configuration** (recommended for most use cases) or **programmatically via JavaScript API** (for advanced/offline scenarios).

## Declarative Configuration (v\<MERMAID_RELEASE_VERSION>+) (Recommended)

The easiest way to use icons in Mermaid is through declarative configuration. This works in browsers, CLI, Live Editor, and headless renders without requiring custom JavaScript.

### Basic Usage

Configure icon packs in your Mermaid config:

```yaml
---
config:
  icons:
    packs:
      logos: "@iconify-json/logos@1"
---
flowchart TB
  A[Start] --> B@{ icon: 'logos:docker', label: 'Docker' }
  B --> C[End]
```

Or in JavaScript:

```js
mermaid.initialize({
  icons: {
    packs: {
      logos: '@iconify-json/logos@1',
      'simple-icons': '@iconify-json/simple-icons@1',
    },
  },
});
```

### Package Spec Format

Icon packs are specified using **package specs** with version pinning:

- Format: `@scope/package@<version>` or `package@<version>`
- **Must include at least a major version** (e.g., `@iconify-json/logos@1`)
- Minor and patch versions are optional (e.g., `@iconify-json/logos@1.2.3`)

**Important**: Only package specs are supported. Direct URLs are not allowed for security reasons.

### Configuration Options

```yaml
icons:
  packs:
    # Icon pack configuration
    # Key: local name to use in diagrams
    # Value: package spec with version
    logos: '@iconify-json/logos@1'
    'simple-icons': '@iconify-json/simple-icons@1'

  # CDN template for resolving package specs
  # Must contain ${packageSpec} placeholder
  cdnTemplate: 'https://cdn.jsdelivr.net/npm/${packageSpec}/icons.json'

  # Maximum file size in MB for icon pack JSON files
  # Range: 1-10 MB, default: 5 MB
  maxFileSizeMB: 5

  # Network timeout in milliseconds for icon pack fetches
  # Range: 1000-30000 ms, default: 5000 ms
  timeout: 5000

  # List of allowed hosts to fetch icons from
  allowedHosts:
    - 'unpkg.com'
    - 'cdn.jsdelivr.net'
    - 'npmjs.com'
```

### Security Features

- **Host allowlisting**: Only fetch from hosts in `allowedHosts`
- **Size limits**: Maximum file size enforced via `maxFileSizeMB`
- **Timeouts**: Network requests timeout after specified milliseconds
- **HTTPS only**: All remote fetches occur over HTTPS
- **Version pinning**: Package specs must include version for reproducibility

### Examples

#### Using Custom CDN Template

```yaml
---
config:
  icons:
    packs:
      logos: "@iconify-json/logos@1"
    cdnTemplate: "https://unpkg.com/${packageSpec}/icons.json"
---
flowchart TB
  A[Start] --> B@{ icon: 'logos:aws', label: 'AWS' }
```

#### Multiple Icon Packs

```yaml
---
config:
  icons:
    packs:
      logos: "@iconify-json/logos@1"
      "simple-icons": "@iconify-json/simple-icons@1"
---
flowchart TB
  A@{ icon: 'logos:docker', label: 'Docker' } --> B@{ icon: 'simple-icons:github', label: 'GitHub' }
```

#### CLI Usage

Create a `mermaid.json` config file:

```json
{
  "icons": {
    "packs": {
      "logos": "@iconify-json/logos@1"
    }
  }
}
```

Then use it with the CLI:

```bash
mmdc -i diagram.mmd -o diagram.svg --configFile mermaid.json
```

## Programmatic API (v11.1.0+) (Advanced)

For advanced scenarios or offline use, you can register icon packs programmatically:

### Using JSON File from CDN

```js
import mermaid from 'CDN/mermaid.esm.mjs';

mermaid.registerIconPacks([
  {
    name: 'logos',
    loader: () =>
      fetch('https://unpkg.com/@iconify-json/logos@1/icons.json').then((res) => res.json()),
  },
]);
```

### Using Packages with Bundler

Install the icon pack:

```bash
npm install @iconify-json/logos@1
```

#### With Lazy Loading

```js
import mermaid from 'mermaid';

mermaid.registerIconPacks([
  {
    name: 'logos',
    loader: () => import('@iconify-json/logos').then((module) => module.icons),
  },
]);
```

#### Without Lazy Loading

```js
import mermaid from 'mermaid';
import { icons } from '@iconify-json/logos';

mermaid.registerIconPacks([
  {
    name: icons.prefix, // Use the prefix defined in the icon pack
    icons,
  },
]);
```

## Finding Icon Packs

Icon packs available for use can be found at [iconify.design](https://icon-sets.iconify.design/) or [icones.js.org](https://icones.js.org/).

The pack name you register is the **local name** used in diagrams. It can differ from the pack's prefix, allowing you to:

- Use shorter names (e.g., register `@iconify-json/material-design-icons` as `mdi`)
- Load specific packs only when used in diagrams (lazy loading)

## Error Handling

If an icon cannot be found:

- The diagram still renders (non-fatal)
- A fallback icon is displayed
- A warning is logged (visible in CLI stderr or browser console)

## Licensing

Iconify JSON format is MIT licensed, but **individual icons may have varying licenses**. Please verify the licenses of the icon packs you configure before use in production.

Mermaid does **not** redistribute third-party icon assets in the core bundle.