ScreenDetailed: top property

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The top read-only property of the ScreenDetailed interface is a number representing the y-coordinate (top edge) of the total screen area inside the OS virtual screen arrangement, relative to the multi-screen origin.

This is equal to the true top edge, ignoring any OS UI element drawn at the top of the screen. Windows cannot be placed in those areas; to get the top coordinate of the screen area that windows can be placed in, use ScreenDetailed.availTop.

Note: In Firefox, a non-standard implementation of the top property is available on the Screen interface. See the Non-standard example below for usage details, and see the Screen reference page for browser support information relating to the non-standard implementation.


A number.


Window Management API example

// Available in browsers that support the Window Management API
const screenDetails = await window.getScreenDetails();

// Return the absolute top value of the first screen
const screen1Top = screenDetails.screens[0].top;

Non-standard example

// Available in Firefox
// Return the absolute top value of the current screen
const screenTop =;


Window Management
# ref-for-dom-screendetailed-top

Browser compatibility

BCD tables only load in the browser

See also