KeyboardEvent
objects describe a user interaction with the keyboard; each event describes a single interaction between the user and a key (or combination of a key with modifier keys) on the keyboard. The event type (keydown
, keypress
, or keyup
) identifies what kind of keyboard activity occurred.
Note: KeyboardEvent
events just indicate what interaction the user had with a key on the keyboard at a low level, providing no contextual meaning to that interaction. When you need to handle text input, use the input
event instead. Keyboard events may not be fired if the user is using an alternate means of entering text, such as a handwriting system on a tablet or graphics tablet.
<div id="interfaceDiagram" style="display: inline-block; position: relative; width: 100%; padding-bottom: 11.666666666666666%; vertical-align: middle; overflow: hidden;"><svg style="display: inline-block; position: absolute; top: 0; left: 0;" viewbox="-50 0 600 70" preserveAspectRatio="xMinYMin meet"><a xlink:href="https://developer.mozilla.org/en-US/docs/Web/API/Event" target="_top"><rect x="1" y="1" width="75" height="50" fill="#fff" stroke="#D4DDE4" stroke-width="2px" /><text x="38.5" y="30" font-size="12px" font-family="Consolas,Monaco,Andale Mono,monospace" fill="#4D4E53" text-anchor="middle" alignment-baseline="middle">Event</text></a><polyline points="76,25 86,20 86,30 76,25" stroke="#D4DDE4" fill="none"/><line x1="86" y1="25" x2="116" y2="25" stroke="#D4DDE4"/><a xlink:href="https://developer.mozilla.org/en-US/docs/Web/API/UIEvent" target="_top"><rect x="116" y="1" width="75" height="50" fill="#fff" stroke="#D4DDE4" stroke-width="2px" /><text x="153.5" y="30" font-size="12px" font-family="Consolas,Monaco,Andale Mono,monospace" fill="#4D4E53" text-anchor="middle" alignment-baseline="middle">UIEvent</text></a><polyline points="191,25 201,20 201,30 191,25" stroke="#D4DDE4" fill="none"/><line x1="201" y1="25" x2="231" y2="25" stroke="#D4DDE4"/><a xlink:href="https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent" target="_top"><rect x="231" y="1" width="130" height="50" fill="#F4F7F8" stroke="#D4DDE4" stroke-width="2px" /><text x="296" y="30" font-size="12px" font-family="Consolas,Monaco,Andale Mono,monospace" fill="#4D4E53" text-anchor="middle" alignment-baseline="middle">KeyboardEvent</text></a></svg></div>
a:hover text { fill: #0095DD; pointer-events: all;}
Constructor
KeyboardEvent()
- Creates a new
KeyboardEvent
object.
Constants
The KeyboardEvent
interface defines the following constants.
Keyboard locations
The following constants identify which part of the keyboard the key event originates from. They are accessed as KeyboardEvent.DOM_KEY_LOCATION_STANDARD
and so forth.
Constant | Value | Description |
---|---|---|
DOM_KEY_LOCATION_STANDARD
|
0x00 |
The key described by the event is not identified as being located in a particular area of the keyboard; it is not located on the numeric keypad (unless it's the NumLock key), and for keys that are duplicated on the left and right sides of the keyboard, the key is, for whatever reason, not to be associated with that location. Examples include alphanumeric keys on the standard PC 101 US keyboard, the NumLock key, and the space bar. |
DOM_KEY_LOCATION_LEFT
|
0x01 |
The key is one which may exist in multiple locations on the keyboard and, in this instance, is on the left side of the keyboard. Examples include the left Control key, the left Command key on a Macintosh keyboard, or the left Shift key. |
DOM_KEY_LOCATION_RIGHT
|
0x02 |
The key is one which may exist in multiple positions on the keyboard and, in this case, is located on the right side of the keyboard. Examples include the right Shift key and the right Alt key (Option on a Mac keyboard). |
DOM_KEY_LOCATION_NUMPAD
|
0x03 |
The key is located on the numeric keypad, or is a virtual key associated with the numeric keypad if there's more than one place the key could originate from. The NumLock key does not fall into this group and is always encoded with the location Examples include the digits on the numeric keypad, the keypad's Enter key, and the decimal point on the keypad. |
Properties
This interface also inherits properties of its parents, UIEvent
and Event
.
KeyboardEvent.altKey
Read only- Returns a
Boolean
that istrue
if the Alt ( Option or ⌥ on OS X) key was active when the key event was generated. KeyboardEvent.code
Read only- Returns a
DOMString
with the code value of the physical key represented by the event.Warning: This ignores the user's keyboard layout, so that if the user presses the key at the "Y" position in a QWERTY keyboard layout (near the middle of the row above the home row), this will always return "KeyY", even if the user has a QWERTZ keyboard (which would mean the user expects a "Z" and all the other properties would indicate a "Z") or a Dvorak keyboard layout (where the user would expect an "F").
KeyboardEvent.ctrlKey
Read only- Returns a
Boolean
that istrue
if the Ctrl key was active when the key event was generated. KeyboardEvent.isComposing
Read only- Returns a
Boolean
that istrue
if the event is fired between aftercompositionstart
and beforecompositionend
. KeyboardEvent.key
Read only- Returns a
DOMString
representing the key value of the key represented by the event. KeyboardEvent.locale
Read only- Returns a
DOMString
representing a locale string indicating the locale the keyboard is configured for. This may be the empty string if the browser or device doesn't know the keyboard's locale.Note: This does not describe the locale of the data being entered. A user may be using one keyboard layout while typing text in a different language.
KeyboardEvent.location
Read only- Returns a
Number
representing the location of the key on the keyboard or other input device. A list of the constants identifying the locations is shown above in Keyboard locations. KeyboardEvent.metaKey
Read only- Returns a
Boolean
that istrue
if the Meta key (on Mac keyboards, the ⌘ Command key; on Windows keyboards, the Windows key (⊞)) was active when the key event was generated. KeyboardEvent.repeat
Read only- Returns a
Boolean
that istrue
if the key is being held down such that it is automatically repeating. KeyboardEvent.shiftKey
Read only- Returns a
Boolean
that istrue
if the Shift key was active when the key event was generated.
Methods
This interface also inherits methods of its parents, UIEvent
and Event
.
KeyboardEvent.getModifierState()
- Returns a
Boolean
indicating if a modifier key such as Alt, Shift, Ctrl, or Meta, was pressed when the event was created.
Obsolete methods
KeyboardEvent.initKeyEvent()
'- Initializes a
KeyboardEvent
object. This was implemented only by Firefox, and is no longer supported even there; instead, you should use theKeyboardEvent()
constructor. KeyboardEvent.initKeyboardEvent()
'- Initializes a
KeyboardEvent
object. This is now deprecated. You should instead use theKeyboardEvent()
constructor.
Obsolete properties
KeyboardEvent.char
' ' Read only- Returns a
DOMString
representing the character value of the key. If the key corresponds to a printable character, this value is a non-empty Unicode string containing that character. If the key doesn't have a printable representation, this is an empty string.Note: If the key is used as a macro that inserts multiple characters, this attribute's value is the entire string, not just the first character.
KeyboardEvent.charCode
' Read only- Returns a
Number
representing the Unicode reference number of the key; this attribute is used only by thekeypress
event. For keys whosechar
attribute contains multiple characters, this is the Unicode value of the first character in that attribute. In Firefox 26 this returns codes for printable characters.Warning: This attribute is deprecated; you should use
KeyboardEvent.key
instead, if available. KeyboardEvent.keyCode
' Read only- Returns a
Number
representing a system and implementation dependent numerical code identifying the unmodified value of the pressed key.Warning: This attribute is deprecated; you should use
KeyboardEvent.key
instead, if available. KeyboardEvent.keyIdentifier
' ' Read only- This property is non-standard and has been deprecated in favor of
KeyboardEvent.key
. It was part of an old version of DOM Level 3 Events. KeyboardEvent.keyLocation
' ' Read only- This is a non-standard deprecated alias for
KeyboardEvent.location
. It was part of an old version of DOM Level 3 Events. KeyboardEvent.which
' Read only- Returns a
Number
representing a system and implementation dependent numeric code identifying the unmodified value of the pressed key; this is usually the same askeyCode
.Warning: This attribute is deprecated; you should use
KeyboardEvent.key
instead, if available.
Events
The following events are based on the KeyboardEvent
type. They can be delivered to any object which implements GlobalEventHandlers
, including Element
, Document
, and Window
. In the list below, each event links to the documentation for the Document
handler for the event, which applies generally to all of the recipients.
Obsolete events
keypress
'- A key that normally produces a character value has been pressed. This event was highly device-dependent and is obsolete. You should not use it.
Usage notes
There are three types of keyboard events: keydown
, keypress
, and keyup
. For most keys, Gecko dispatches a sequence of key events like this:
- When the key is first pressed, the
keydown
event is sent. - If the key is not a modifier key, the
keypress
event is sent. - When the user releases the key, the
keyup
event is sent.
Special cases
Some keys toggle the state of an indicator light; these include keys such as Caps Lock, Num Lock, and Scroll Lock. On Windows and Linux, these keys dispatch only the keydown
and keyup
events.
On Linux, Firefox 12 and earlier also dispatched the keypress
event for these keys.
However, a limitation of the macOS event model causes Caps Lock to dispatch only the keydown
event. Num Lock was supported on some older laptop models (2007 models and older), but since then, macOS hasn't supported Num Lock even on external keyboards. On older MacBooks with a Num Lock key, that key doesn't generate any key events. Gecko does support the Scroll Lock key if an external keyboard which has an F14 key is connected. In certain older versions of Firefox, this key generated a keypress
event; this inconsistent behavior was bug 602812.
Auto-repeat handling
When a key is pressed and held down, it begins to auto-repeat. This results in a sequence of events similar to the following being dispatched:
keydown
keypress
keydown
keypress
- <<repeating until the user releases the key>>
keyup
This is what the DOM Level 3 specification says should happen. There are some caveats, however, as described below.
Auto-repeat on some GTK environments such as Ubuntu 9.4
In some GTK-based environments, auto-repeat dispatches a native key-up event automatically during auto-repeat, and there's no way for Gecko to know the difference between a repeated series of keypresses and an auto-repeat. On those platforms, then, an auto-repeat key will generate the following sequence of events:
keydown
keypress
keyup
keydown
keypress
keyup
- <<repeating until the user releases the key>>
keyup
In these environments, unfortunately, there's no way for web content to tell the difference between auto-repeating keys and keys that are just being pressed repeatedly.
Auto-repeat handling prior to Gecko 5.0
Before Gecko 5.0 (Firefox 5.0 / Thunderbird 5.0 / SeaMonkey 2.2), keyboard handling was less consistent across platforms.
- Windows
- Auto-repeat behavior is the same as in Gecko 4.0 and later.
- Mac
- After the initial keydown event, only keypress events are sent until the keyup event occurs; the inter-spaced keydown events are not sent.
- Linux
- The event behavior depends on the specific platform. It will either behave like Windows or Mac depending on what the native event model does.
Note: Manually firing an event does not generate the default action associated with that event. For example, manually firing a key event does not cause that letter to appear in a focused text input. In the case of UI events, this is important for security reasons, as it prevents scripts from simulating user actions that interact with the browser itself.
Example
<!DOCTYPE html>
<html>
<head>
<script>
'use strict';
document.addEventListener('keydown', (event) => {
const keyName = event.key;
if (keyName === 'Control') {
// do not alert when only Control key is pressed.
return;
}
if (event.ctrlKey) {
// Even though event.key is not 'Control' (e.g., 'a' is pressed),
// event.ctrlKey may be true if Ctrl key is pressed at the same time.
alert(`Combination of ctrlKey + ${keyName}`);
} else {
alert(`Key pressed ${keyName}`);
}
}, false);
document.addEventListener('keyup', (event) => {
const keyName = event.key;
// As the user releases the Ctrl key, the key is no longer active,
// so event.ctrlKey is false.
if (keyName === 'Control') {
alert('Control key was released');
}
}, false);
</script>
</head>
<body>
</body>
</html>
Specifications
Specification | Status | Comment |
---|---|---|
UI EventsThe definition of 'KeyboardEvent' in that specification. | Working Draft |
The KeyboardEvent
interface specification went through numerous draft versions, first under DOM Events Level 2 where it was dropped as no consensus arose, then under DOM Events Level 3. This led to the implementation of non-standard initialization methods, the early DOM Events Level 2 version, KeyboardEvent.initKeyEvent()
by Gecko browsers and the early DOM Events Level 3 version, KeyboardEvent.initKeyboardEvent()
by others. Both have been superseded by the modern usage of a constructor: KeyboardEvent()
.
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
KeyboardEvent
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 1.5 |
IE
Full support 9 |
Opera
Full support 12.1 |
Safari
Full support 3.1 |
WebView Android
Full support 1 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 12.1 |
Safari iOS
Full support 2 |
Samsung Internet Android
Full support 1.0 |
DOM_KEY_LOCATION_LEFT
|
Chrome
Full support Yes |
Edge
Full support ≤18 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
DOM_KEY_LOCATION_NUMPAD
|
Chrome
Full support Yes |
Edge
Full support ≤18 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
DOM_KEY_LOCATION_RIGHT
|
Chrome
Full support Yes |
Edge
Full support ≤18 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
DOM_KEY_LOCATION_STANDARD
|
Chrome
Full support Yes |
Edge
Full support ≤18 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
KeyboardEvent() constructor
|
Chrome
Full support Yes |
Edge
Full support ≤79 |
Firefox
Full support 31 |
IE
No support No |
Opera
Full support Yes |
Safari
? |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support 31 |
Opera Android
Full support Yes |
Safari iOS
? |
Samsung Internet Android
Full support Yes |
altKey
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support Yes |
IE
Full support Yes |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
Chrome
Full support 26 |
Edge
Full support 12 |
Firefox
Full support 3 |
IE
Full support 9 |
Opera
Full support 12.1 |
Safari
Full support 5.1 |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support 5.1 |
Samsung Internet Android
Full support Yes | |
code
|
Chrome
Full support 48 |
Edge
Full support 79 |
Firefox
Full support 38 |
IE
No support No |
Opera
Full support 35 |
Safari
Full support 10 |
WebView Android
Full support 48 |
Chrome Android
Full support 48 |
Firefox Android
Full support 38 |
Opera Android
Full support 35 |
Safari iOS
Full support 10 |
Samsung Internet Android
Full support 5.0 |
ctrlKey
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support Yes |
IE
Full support Yes |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
getModifierState
|
Chrome
Full support 31 |
Edge
Full support 12 |
Firefox
Full support 15 |
IE
Full support 9 |
Opera
Full support 17 |
Safari
Full support 10.1 |
WebView Android
Full support 4.4.3 |
Chrome Android
Full support 31 |
Firefox Android
Full support 15 |
Opera Android
Full support 18 |
Safari iOS
Full support 10.3 |
Samsung Internet Android
Full support 2.0 |
isComposing
|
Chrome
Full support 56 |
Edge
Full support ≤79 |
Firefox
Full support 31 |
IE
No support No |
Opera
Full support 43 |
Safari
Full support 10.1 |
WebView Android
Full support 56 |
Chrome Android
Full support 56 |
Firefox Android
Full support 31 |
Opera Android
Full support 43 |
Safari iOS
Full support 10.3 |
Samsung Internet Android
Full support 6.0 |
key
|
Chrome
Full support 51 |
Edge
Full support 12 |
Firefox
Full support 23 |
IE Full support 9 Full support 9 Notes' IE's implementation does not completely match the current spec because it is based on an older version of the spec. |
Opera
Full support 38 |
Safari
Full support 10 |
WebView Android
Full support 51 |
Chrome Android
Full support 51 |
Firefox Android
Full support 23 |
Opera Android
Full support 41 |
Safari iOS
Full support 10 |
Samsung Internet Android
Full support 5.0 |
Chrome
Full support 26 |
Edge
Full support 12 |
Firefox
Full support 3 |
IE
Full support 9 |
Opera
Full support 12.1 |
Safari
Full support 5 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 26 |
Firefox Android
Full support 4 |
Opera Android
Full support 12.1 |
Safari iOS
Full support 5.1 |
Samsung Internet Android
Full support 1.5 | |
Chrome
No support 26 — 54 |
Edge
? |
Firefox
No support No |
IE
No support No |
Opera
No support 15 — 41 |
Safari
Full support 5.1 |
WebView Android
No support ? — 54 |
Chrome Android
No support 26 — 54 |
Firefox Android
No support No |
Opera Android
No support ? — 41 |
Safari iOS
Full support 5.1 |
Samsung Internet Android
No support 1.5 — 6.0 | |
location
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support 15 |
IE
Full support 9 |
Opera
Full support Yes |
Safari
Full support 6.1 |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support 15 |
Opera Android
Full support Yes |
Safari iOS
Full support 8 |
Samsung Internet Android
Full support Yes |
metaKey
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support Yes |
IE
Full support Yes |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
repeat
|
Chrome
Full support Yes |
Edge
Full support 79 |
Firefox
Full support 28 |
IE
No support No |
Opera
Full support Yes |
Safari
Full support 10.1 |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support 28 |
Opera Android
Full support Yes |
Safari iOS
Full support 10.3 |
Samsung Internet Android
Full support Yes |
shiftKey
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support Yes |
IE
Full support Yes |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
Full support Yes |
Samsung Internet Android
Full support Yes |
Chrome
Full support 4 |
Edge
Full support 12 |
Firefox Full support 2 Full support 2 Notes' Firefox also implements this property on the |
IE
Full support 9 |
Opera
Full support 12.1 |
Safari
Full support 5.1 |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android Full support Yes Full support Yes Notes' Firefox also implements this property on the |
Opera Android
Full support 12.1 |
Safari iOS
Full support 5.1 |
Samsung Internet Android
Full support Yes |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- Non-standard. Expect poor cross-browser support.'
- Non-standard. Expect poor cross-browser support.
- Deprecated. Not for use in new websites.'
- Deprecated. Not for use in new websites.
- See implementation notes.'
- See implementation notes.
Compatibility notes
- As of Firefox 65, the
keypress
event is no longer fired for non-printable keys (bug 968056), except for the Enter key, and the Shift + Enter and Ctrl + Enter key combinations (these were kept for cross-browser compatibility purposes).
See also
KeyboardEvent by Mozilla Contributors is licensed under CC-BY-SA 2.5.