MNotes/components-wiki/radio.md

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<!-- catalog-only-start --><!-- ---
name: Radio
dirname: radio
ssrOnly: true
-----><!-- catalog-only-end -->
<catalog-component-header image-align="start">
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# Radio button
<!--*
# Document freshness: For more information, see go/fresh-source.
freshness: { owner: 'lizmitchell' reviewed: '2025-05-20' }
tag: 'docType:reference'
*-->
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<!-- go/md-radio -->
<!-- [TOC] -->
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[Radio buttons](https://m3.material.io/components/radio-button)<!-- {.external} --> let
people select one option from a set of options.
</catalog-component-header-title>
<img
class="hero"
src="images/radio/hero.webp"
alt="A list of items with radio buttons and one selected."
title="Radio buttons">
</catalog-component-header>
* [Design article](https://m3.material.io/components/radio-button) <!-- {.external} -->
* [API Documentation](#api)
* [Source code](https://github.com/material-components/material-web/tree/main/radio)
<!-- {.external} -->
<!-- catalog-only-start -->
<!--
## Interactive Demo
{% playgroundexample dirname=dirname %}
-->
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## Usage
Radios behave like
[`<input type="radio">`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/radio)<!-- {.external} -->
elements and form a group with the same `name` attribute. Only one radio can be
selected in a group.
Radios can be pre-selected by adding a `checked` attribute.
Add a `value` to identify which radio is selected in a form.
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<!-- Need to add catalog-include "figures/<component>/usage.html" -->
```html
<form>
<md-radio name="animals" value="cats"></md-radio>
<md-radio name="animals" value="dogs"></md-radio>
<md-radio name="animals" value="birds" checked></md-radio>
</form>
```
### Label
Associate a label with a radio using the `<label>` element.
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```html
<md-radio id="cats-radio" name="animals" value="cats"></md-radio>
<label for="cats-radio">Cats</label>
<md-radio id="dogs-radio" name="animals" value="dogs"></md-radio>
<label for="dogs-radio">Dogs</label>
```
> Note: do not wrap radios inside of a `<label>`, which stops screen readers
> from correctly announcing the number of radios in a group.
## Accessibility
Add an
[`aria-label`](https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Attributes/aria-label)<!-- {.external} -->
attribute to radios without labels or radios whose labels need to be more
descriptive.
Place radios inside a
[`role="radiogroup"`](https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/radiogroup_role)<!-- {.external} -->.
Radio groups must display a label, either with `aria-label` or
`aria-labelledby`.
```html
<div role="radiogroup" aria-labelledby="group-title">
<h3 id="group-title">Starting position</h3>
<div>
<md-radio id="first-radio" name="group" value="1"
aria-label="First"></md-radio>
<label for="first-radio">1st</label>
</div>
<div>
<md-radio id="second-radio" name="group" value="2"
aria-label="Second"></md-radio>
<label for="second-radio">2nd</label>
</div>
</div>
```
> Note: radios are not automatically labelled by `<label>` elements and always
> need an `aria-label`. See b/294081528.
## Theming
Radios support [Material theming](../theming/README.md) and can be customized in
terms of color.
### Tokens
Token | Default value
-------------------------------- | -----------------------------------
`--md-radio-icon-color` | `--md-sys-color-on-surface-variant`
`--md-radio-selected-icon-color` | `--md-sys-color-primary`
`--md-radio-icon-size` | `20px`
* [All tokens](https://github.com/material-components/material-web/blob/main/tokens/_md-comp-radio.scss)
<!-- {.external} -->
### Example
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<!-- Need to add catalog-include "figures/<component>/usage.html" -->
```html
<style>
:root {
--md-sys-color-primary: #006A6A;
--md-radio-icon-size: 16px;
}
</style>
<md-radio name="group"></md-radio>
<md-radio name="group" checked></md-radio>
<md-radio name="group"></md-radio>
```
<!-- auto-generated API docs start -->
## API
### MdRadio <code>&lt;md-radio&gt;</code>
#### Properties
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| Property | Attribute | Type | Default | Description |
| --- | --- | --- | --- | --- |
| `required` | `required` | `boolean` | `false` | Whether or not the radio is required. If any radio is required in a group, all radios are implicitly required. |
| `value` | `value` | `string` | `'on'` | The element value to use in form submission when checked. |
| `checked` | `checked` | `boolean` | `undefined` | |
| `disabled` | | `boolean` | `undefined` | |
| `name` | | `string` | `undefined` | |
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#### Methods
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| Method | Parameters | Returns | Description |
| --- | --- | --- | --- |
| `formResetCallback` | _None_ | `void` | |
| `formStateRestoreCallback` | `state` | `void` | |
<!-- mdformat on(autogenerated might break rendering in catalog) -->
#### Events
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| Event | Type | [Bubbles](https://developer.mozilla.org/en-US/docs/Web/API/Event/bubbles) | [Composed](https://developer.mozilla.org/en-US/docs/Web/API/Event/composed) | Description |
| --- | --- | --- | --- | --- |
| `input` | `InputEvent` | Yes | No | Dispatched when the value changes from user interaction. |
| `change` | `Event` | Yes | Yes | Dispatched when the value changes from user interaction. |
<!-- mdformat on(autogenerated might break rendering in catalog) -->
<!-- auto-generated API docs end -->