CSS border-bottom-width Property

Description

The border-bottom-width CSS property controls the thickness or width of the bottom border of an element. It is part of the set of properties used to customize the appearance of borders around elements, such as divs or paragraphs, on a webpage. By specifying a numerical value (in pixels, ems, rems, or other valid units), you can determine how thick the bottom border of the element should be. This property allows for precise control over the visual presentation of borders, helping to define the element's overall look and feel.

Initial value: medium
Applies to: All elements
Inherited: No
Computed value: Absolute length; '0' if the border style is 'none' or 'hidden'
Animatable: Yes
JavaScript syntax: object.style.borderBottomWidth

Interactive Demo

border-bottom-width: 4px;

border-bottom-width: 1em;

border-bottom-width: thick;

border-bottom-width: 9mm;

border-bottom-width: transparent;

The rusty swing set creaked a lonely lullaby in the twilight, shadows lengthening like grasping fingers across the dew-kissed grass. A lone dandelion seed, adrift on the breeze, whispered secrets of faraway fields, of dandelion suns and galaxies spun from fluff. Somewhere, beyond the veil of dusk, a coyote laughed, echoing through the stillness like a forgotten memory.

Syntax

border-bottom-width: <line-width>

Values

<line-width> = <length> | thin | medium | thick

thinLess than the default width.
mediumDefault value.
thickGreater than the default width.
<length>Floating-point number, followed by an absolute units designator (cm, mm, in, pt, or pc) or a relative units designator (em, ex, or px).
inherit

Example

HTML

<div class="border">This is an example of the border-bottom-width property using a red solid border 3px in width.</div>

CSS

.border {
   border: 1px solid blue;
   border-bottom-style: solid;
   border-bottom-width: 3px;
   border-bottom-color: red;
   margin: 20px;
   padding: 20px;
}

Result

Editor