This property determines the order in which a GuiObject|GUI renders to the screen relative to other GUIs.

By default, GUIs render in ascending priority order where lower values are rendered first. As a result, GUIs with lower ZIndex values appear under higher values. You can change the render order by changing the value of ScreenGui.ZIndexBehavior.

The range of valid values is -MAX_INT to MAX_INT, inclusive (2,147,483,647 or (2^31 - 1)). If you are unsure if you will need to layer an element between two already-existing elements in the future, it can be a good idea to use multiples of 100, i.e. 0, 100, 200. This ensures a large gap of ZIndex values you can use for elements rendered in-between other elements.

See also

• GuiObject/LayoutOrder, which controls the sort order of a GUI when used with a UIGridStyleLayout instead of render order.