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This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Returns the first available pixel available from the left side of the screen.


iAvail = window.screen.availLeft


setY = window.screen.height - window.screen.availTop;
setX = window.screen.width - window.screen.availLeft;
window.moveTo(setX, setY);


In most cases, this property returns 0.

If you work with two screens this property, evaluated on the right screen, returns the width of the left one in pixels (thereby indicating the X coordinate of the left edge of the screen on the right).

On Windows, this property depends on which screen is set as your primary, returning the X coordinate of the leftmost available pixel relative to the primary screen. That is, the primary screen's left edge always has the X coordinate 0, even if it's not the leftmost screen. If the secondary screen is to the left of the primary screen, it has a negative X coordinate to compensate:

[1] [2] - on left screen availLeft returns 0, on the right screen it returns the width of the left one

[2] [1] - on left screen availLeft returns -width of that screen, on the right screen, it returns 0

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 Last updated by: cvrebert,