Document: keydown event

The keydown event is fired when a key is pressed.

Unlike the keypress event, the keydown event is fired for all keys, regardless of whether they produce a character value.

Bubbles Yes
Cancelable Yes
Interface KeyboardEvent
Event handler property onkeydown

The keydown and keyup events provide a code indicating which key is pressed, while keypress indicates which character was entered. For example, a lowercase "a" will be reported as 65 by keydown and keyup, but as 97 by keypress. An uppercase "A" is reported as 65 by all events.

Since Firefox 65, the keydown and keyup events are now fired during IME composition (bug 354358). To ignore all keydown events that are part of composition, do something like this (229 is a special value set for a keyCode relating to an event that has been processed by an IME):

eventTarget.addEventListener("keydown", event => {
  if (event.isComposing || event.keyCode === 229) {
  // do something


addEventListener keydown example

This example logs the KeyboardEvent.code value whenever you press down a key.

<p>Focus the IFrame first (e.g. by clicking in it), then try pressing some keys.</p>
<p id="log"></p>
document.addEventListener('keydown', logKey);

function logKey(e) {
  log.textContent += ` ${e.code}`;

onkeydown equivalent

document.onkeydown = logKey;


Specification Status
UI Events Working Draft

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
keydown eventChrome Full support 1Edge Full support 12Firefox Full support 14IE Full support 9Opera Full support 11.6Safari Full support 2WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 14Opera Android Full support 12Safari iOS Full support 1Samsung Internet Android Full support 1.0


Full support  
Full support

See also