Window.innerWidth

The read-only Window property innerWidth returns the interior width of the window in pixels. This includes the width of the vertical scroll bar, if one is present.

More precisely, innerWidth returns the width of the window's layout viewport. The interior height of the window—the height of the layout viewport—can be obtained from the innerHeight property.

Syntax

let intViewportWidth = window.innerWidth;

Value

An integer value indicating the width of the window's layout viewport in pixels. This property is read-only, and has no default value.

To change the window's width, use one of the Window methods for resizing windows, such as resizeBy() or resizeTo().

Usage notes

If you need to obtain the width of the window minus the scrollbar and borders, use the root <html> element's clientWidth property instead.

The innerWidth property is available on any window or object that behaves like a window, such as a frame or tab.

Example

// This will return the width of the viewport
var intFrameWidth = window.innerWidth;

// This will return the width of the frame viewport within a frameset
var intFrameWidth = self.innerWidth;

// This will return the width of the viewport of the closest frameset
var intFramesetWidth = parent.innerWidth;

// This will return the width of the viewport of the outermost frameset
var intOuterFramesetWidth = top.innerWidth;

Specification

Specification Status Comment
CSS Object Model (CSSOM) View Module
The definition of 'window.innerWidth' in that specification.
Working Draft Initial definition

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
innerWidthChrome Full support 1Edge Full support 12Firefox Full support 1
Full support 1
No support 4 — 24
Notes
Notes This property was buggy and could give a wrong value before page load in certain circumstances, see bug 641188.
IE Full support 9Opera Full support 9Safari Full support 3WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4
Full support 4
No support 4 — 24
Notes
Notes This property was buggy and could give a wrong value before page load in certain circumstances, see bug 641188.
Opera Android Full support 10.1Safari iOS Full support 1Samsung Internet Android Full support 1.0

Legend

Full support  
Full support
See implementation notes.
See implementation notes.

See also