Plugins are the most efficient way to customize or change the default behavior of a chart. They have been introduced at [version 2.1.0](https://github.com/chartjs/Chart.js/releases/tag/2.1.0) (global plugins only) and extended at [version 2.5.0](https://github.com/chartjs/Chart.js/releases/tag/v2.5.0) (per chart plugins and options).
Plugins can also be defined directly in the chart `plugins` config (a.k.a. *inline plugins*):
```javascript
var chart = new Chart(ctx, {
plugins: [{
beforeInit: function(chart, options) {
//..
}
}]
});
```
However, this approach is not ideal when the customization needs to apply to many charts.
## Global plugins
Plugins can be registered globally to be applied on all charts (a.k.a. *global plugins*):
```javascript
Chart.plugins.register({
// plugin implementation
});
```
> Note: *inline* plugins can't be registered globally.
## Configuration
### Plugin ID
Plugins must define a unique id in order to be configurable.
This id should follow the [npm package name convention](https://docs.npmjs.com/files/package.json#name):
- can't start with a dot or an underscore
- can't contain any non-URL-safe characters
- can't contain uppercase letters
- should be something short, but also reasonably descriptive
If a plugin is intended to be released publicly, you may want to check the [registry](https://www.npmjs.com/search?q=chartjs-plugin-) to see if there's something by that name already. Note that in this case, the package name should be prefixed by `chartjs-plugin-` to appear in Chart.js plugin registry.
### Plugin options
Plugin options are located under the `options.plugins` config and are scoped by the plugin ID: `options.plugins.{plugin-id}`.