Style borderBottomWidth Property

Change the width of the bottom border of a <div> element to 10px:

document.getElementById("myDiv").style.borderBottomWidth = "10px";

More "Try it Yourself" examples below.

Description

The borderBottomWidth property sets or returns the width of the bottom border of an element.

The numbers in the table specify the first browser version that fully supports the property.

Property
borderBottomWidth	1.0	4.0	1.0	1.0	3.5

Return the borderBottomWidth property:

object.style.borderBottomWidth

Set the borderBottomWidth property:

Value	Description
thin	Defines a thin border
medium	Defines a medium border. This is default
thick	Defines a thick border
length	The width of the border in length units
initial	Sets this property to its default value. Read about initial
inherit	Inherits this property from its parent element. Read about inherit

Default Value:	medium
Return Value:	A String, representing the width of an element's bottom border
CSS Version	CSS1

Change the width of the bottom border of a <div> element to thin:

document.getElementById("myDiv").style.borderBottomWidth = "thin";

Return the width of the bottom border of a <div> element:

alert(document.getElementById("myDiv").style.borderBottomWidth);

CSS tutorial: CSS Border

HTML DOM reference: border property