KeyboardEvent.key

The KeyboardEvent.key read-only property returns the value of a key or keys pressed by the user. It will be one of the following values:

• If the value has a printed representation, it will be a non-empty Unicode character string.
• If the value is a control key, one of the pre-defined key values.
• If the event is caused by a dead key press, the key value must be "Dead".
• If more than one key is pressed and the combination includes a modifier that would make the combination non printing, it will be the printable character. For example, if the combination were 'Control' + 'a', the 'a' will be returned.
• If the value cannot be identified, 'Unidentified' will be returned.

Example

window.addEventListener("keydown", function (event) {
  if (event.defaultPrevented) {
    return; // Should do nothing if the key event was already consumed.
  }

  switch (event.key) {
    case "ArrowDown":
      // Do something for "down arrow" key press.
      break;
    case "ArrowUp":
      // Do something for "up arrow" key press.
      break;
    case "ArrowLeft":
      // Do something for "left arrow" key press.
      break;
    case "ArrowRight":
      // Do something for "right arrow" key press.
      break;
    case "Enter":
      // Do something for "enter" or "return" key press.
      break;
    case "Escape":
      // Do something for "esc" key press.
      break;
    default:
      return; // Quit when this doesn't handle the key event.
  }

  // Consume the event for suppressing "double action".
  event.preventDefault();
}, true);

Specification

Browser compatibility

[1]: Internet Explorer's implementation does not completely match the current spec because it is based on an older version of the spec.

[2]: WebKit bug #69029

Key values

Following tables show what key values are used for each native virtual keycode.

Key values on Windows (and char values of IE)

Key values of WM_APPCOMMAND message on Windows

On Windows, some keys on multimedia keyboard don't cause WM_KEYDOWN nor WM_KEYUP message. Instead, WM_APPCOMMAND is fired. If WM_APPCOMMAND is caused by a key press, Gecko dispatches DOM keyboard events starting from 37 (bug 865561).

Key values on Mac

Key values on Android and Firefox OS

Key values on Linux (GTK/XKB)

Key values on Qt toolkit