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.


let availLeft = window.screen.availLeft;


let setX = window.screen.width - window.screen.availLeft;
let setY = window.screen.height - window.screen.availTop;
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

Browser compatibility

ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Chrome Full support YesEdge Full support 79Firefox Full support YesIE ? Opera Full support YesSafari Full support 6WebView Android Full support YesChrome Android Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS ? Samsung Internet Android Full support Yes


Full support
Full support
Compatibility unknown
Compatibility unknown
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.