ion-checkbox

shadow

Checkboxes allow the selection of multiple options from a set of options. They appear as checked (ticked) when activated. Clicking on a checkbox will toggle the checked property. They can also be checked programmatically by setting the checked property.

Basic Usage

Label Placement

Developers can use the labelPlacement property to control how the label is placed relative to the control.

Justification

Developers can use the justify property to control how the label and control are packed on a line.

note

ion-item is only used in the demos to emphasize how justify works. It is not needed in order for justify to function correctly.

Indeterminate Checkboxes

Theming

CSS Custom Properties

Interfaces

CheckboxChangeEventDetail

interface CheckboxChangeEventDetail<T = any> {
  value: T;
  checked: boolean;
}

CheckboxCustomEvent

While not required, this interface can be used in place of the CustomEvent interface for stronger typing with Ionic events emitted from this component.

interface CheckboxCustomEvent<T = any> extends CustomEvent {
  detail: CheckboxChangeEventDetail<T>;
  target: HTMLIonCheckboxElement;
}

Migrating from Legacy Checkbox Syntax

A simpler checkbox syntax was introduced in Ionic 7.0. This new syntax reduces the boilerplate required to setup a checkbox, resolves accessibility issues, and improves the developer experience.

Developers can perform this migration one checkbox at a time. While developers can continue using the legacy syntax, we recommend migrating as soon as possible.

Using the Modern Syntax

Using the modern syntax involves removing the ion-label and passing the label directly inside of ion-checkbox. The placement of the label can be configured using the labelPlacement property on ion-checkbox. The way the label and the control are packed on a line can be controlled using the justify property on ion-checkbox.

JavaScript

<!-- Basic -->

<!-- Before -->
<ion-item>
  <ion-label>Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox>Checkbox Label</ion-checkbox>
</ion-item>

<!-- Fixed Labels -->

<!-- Before -->
<ion-item>
  <ion-label position="fixed">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox label-placement="fixed">Checkbox Label</ion-checkbox>
</ion-item>

<!-- Checkbox at the start of line, Label at the end of line -->

<!-- Before -->
<ion-item>
  <ion-label slot="end">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox label-placement="end">Checkbox Label</ion-checkbox>
</ion-item>

Angular

<!-- Basic -->

<!-- Before -->
<ion-item>
  <ion-label>Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox>Checkbox Label</ion-checkbox>
</ion-item>

<!-- Fixed Labels -->

<!-- Before -->
<ion-item>
  <ion-label position="fixed">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox labelPlacement="fixed">Checkbox Label</ion-checkbox>
</ion-item>

<!-- Checkbox at the start of line, Label at the end of line -->

<!-- Before -->
<ion-item>
  <ion-label slot="end">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox labelPlacement="end">Checkbox Label</ion-checkbox>
</ion-item>

React

{/* Basic */}

{/* Before */}
<IonItem>
  <IonLabel>Checkbox Label</IonLabel>
  <IonCheckbox></IonCheckbox>
</IonItem>

{/* After */}
<IonItem>
  <IonCheckbox>Checkbox Label</IonCheckbox>
</IonItem>

{/* Fixed Labels */}

{/* Before */}
<IonItem>
  <IonLabel position="fixed">Checkbox Label</IonLabel>
  <IonCheckbox></IonCheckbox>
</IonItem>

{/* After */}
<IonItem>
  <IonCheckbox labelPlacement="fixed">Checkbox Label</IonCheckbox>
</IonItem>

{/* Checkbox at the start of line, Label at the end of line */}

{/* Before */}
<IonItem>
  <IonLabel slot="end">Checkbox Label</IonLabel>
  <IonCheckbox></IonCheckbox>
</IonItem>

{/* After */}
<IonItem>
  <IonCheckbox labelPlacement="end">Checkbox Label</IonCheckbox>
</IonItem>

Vue

<!-- Basic -->

<!-- Before -->
<ion-item>
  <ion-label>Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox>Checkbox Label</ion-checkbox>
</ion-item>

<!-- Fixed Labels -->

<!-- Before -->
<ion-item>
  <ion-label position="fixed">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox label-placement="fixed">Checkbox Label</ion-checkbox>
</ion-item>

<!-- Checkbox at the start of line, Label at the end of line -->

<!-- Before -->
<ion-item>
  <ion-label slot="end">Checkbox Label</ion-label>
  <ion-checkbox></ion-checkbox>
</ion-item>

<!-- After -->
<ion-item>
  <ion-checkbox label-placement="end">Checkbox Label</ion-checkbox>
</ion-item>

note

In past versions of Ionic, ion-item was required for ion-checkbox to function properly. Starting in Ionic 7.0, ion-checkbox should only be used in an ion-item when the item is placed in an ion-list. Additionally, ion-item is no longer required for ion-checkbox to function properly.

Using the Legacy Syntax

Ionic uses heuristics to detect if an app is using the modern checkbox syntax. In some instances, it may be preferable to continue using the legacy syntax. Developers can set the legacy property on ion-checkbox to true to force that instance of the checkbox to use the legacy syntax.

Properties

alignment

Description	How to control the alignment of the checkbox and label on the cross axis. "start": The label and control will appear on the left of the cross axis in LTR, and on the right side in RTL. "center": The label and control will appear at the center of the cross axis in both LTR and RTL.
Attribute	alignment
Type	"center" ｜ "start"
Default	'center'

checked

Description	If true, the checkbox is selected.
Attribute	checked
Type	boolean
Default	false

color

Description	The color to use from your application's color palette. Default options are: "primary", "secondary", "tertiary", "success", "warning", "danger", "light", "medium", and "dark". For more information on colors, see theming.
Attribute	color
Type	"danger" ｜ "dark" ｜ "light" ｜ "medium" ｜ "primary" ｜ "secondary" ｜ "success" ｜ "tertiary" ｜ "warning" ｜ string ｜ undefined
Default	undefined

disabled

Description	If true, the user cannot interact with the checkbox.
Attribute	disabled
Type	boolean
Default	false

indeterminate

Description	If true, the checkbox will visually appear as indeterminate.
Attribute	indeterminate
Type	boolean
Default	false

justify

Description	How to pack the label and checkbox within a line. "start": The label and checkbox will appear on the left in LTR and on the right in RTL. "end": The label and checkbox will appear on the right in LTR and on the left in RTL. "space-between": The label and checkbox will appear on opposite ends of the line with space between the two elements.
Attribute	justify
Type	"end" ｜ "space-between" ｜ "start"
Default	'space-between'

labelPlacement

Description	Where to place the label relative to the checkbox. "start": The label will appear to the left of the checkbox in LTR and to the right in RTL. "end": The label will appear to the right of the checkbox in LTR and to the left in RTL. "fixed": The label has the same behavior as "start" except it also has a fixed width. Long text will be truncated with ellipses ("..."). "stacked": The label will appear above the checkbox regardless of the direction. The alignment of the label can be controlled with the alignment property.
Attribute	label-placement
Type	"end" ｜ "fixed" ｜ "stacked" ｜ "start"
Default	'start'

legacy

Description	Set the legacy property to true to forcibly use the legacy form control markup. Ionic will only opt checkboxes in to the modern form markup when they are using either the aria-label attribute or have text in the default slot. As a result, the legacy property should only be used as an escape hatch when you want to avoid this automatic opt-in behavior. Note that this property will be removed in an upcoming major release of Ionic, and all form components will be opted-in to using the modern form markup.
Attribute	legacy
Type	boolean ｜ undefined
Default	undefined

mode

Description	The mode determines which platform styles to use.
Attribute	mode
Type	"ios" ｜ "md"
Default	undefined

name

Description	The name of the control, which is submitted with the form data.
Attribute	name
Type	string
Default	this.inputId

value

Description	The value of the checkbox does not mean if it's checked or not, use the checked property for that. The value of a checkbox is analogous to the value of an <input type="checkbox">, it's only used when the checkbox participates in a native <form>.
Attribute	value
Type	any
Default	'on'

Events

Name	Description
ionBlur	Emitted when the checkbox loses focus.
ionChange	Emitted when the checked property has changed as a result of a user action such as a click. This event will not emit when programmatically setting the checked property.
ionFocus	Emitted when the checkbox has focus.

Methods

No public methods available for this component.

CSS Shadow Parts

Name	Description
container	The container for the checkbox mark.
mark	The checkmark used to indicate the checked state.

CSS Custom Properties

Name	Description
--border-color	Border color of the checkbox icon
--border-color-checked	Border color of the checkbox icon when checked
--border-radius	Border radius of the checkbox icon
--border-style	Border style of the checkbox icon
--border-width	Border width of the checkbox icon
--checkbox-background	Background of the checkbox icon
--checkbox-background-checked	Background of the checkbox icon when checked
--checkmark-color	Color of the checkbox checkmark when checked
--checkmark-width	Stroke width of the checkbox checkmark
--size	Size of the checkbox icon
--transition	Transition of the checkbox icon

Slots

Name	Description
``	The label text to associate with the checkbox. Use the "labelPlacement" property to control where the label is placed relative to the checkbox.