MouseEvent altKey Property

Was the "ALT" key pressed when the mouse button was clicked:

if (event.altKey) {
text = "The ALT key was pressed!";
} else {
text = "The ALT key was NOT pressed!";
}

Description

The altKey property returns true if the ALT key is pressed when a mouse event occurs.

Otherwise it returns false.

The altKey property is read-only.

On some keyboards, the ALT key is displayed as Option or Opt.

event.altKey

Return Value:	A Boolean. Returns `true` if the ALT key is pressed when a mouse event occurs. Otherwise it returns `false`.
DOM Version:	DOM Level 2 Mouse Events.

event.altkey is a DOM Level 2 (2001) feature.

It is fully supported in all browsers:


Chrome	Edge	Firefox	Safari	Opera	IE
Yes	Yes	Yes	Yes	Yes	9-11