Easily make an element as wide or as tall with our width and height utilities.

Relative to the parent

Width and height utilities are generated from the utility API in _utilities.scss. Includes support for 25%, 50%, 75%, 100%, and auto by default. Modify those values as you need to generate different utilities here.

Width 25%
Width 50%
Width 75%
Width 100%
Width auto
<div class="w-25 p-3" style="background-color: #eee;">Width 25%</div>
<div class="w-50 p-3" style="background-color: #eee;">Width 50%</div>
<div class="w-75 p-3" style="background-color: #eee;">Width 75%</div>
<div class="w-100 p-3" style="background-color: #eee;">Width 100%</div>
<div class="w-auto p-3" style="background-color: #eee;">Width auto</div>
Height 25%
Height 50%
Height 75%
Height 100%
Height auto
<div style="height: 100px; background-color: rgba(255,0,0,0.1);">
  <div class="h-25 d-inline-block" style="width: 120px; background-color: rgba(0,0,255,.1)">Height 25%</div>
  <div class="h-50 d-inline-block" style="width: 120px; background-color: rgba(0,0,255,.1)">Height 50%</div>
  <div class="h-75 d-inline-block" style="width: 120px; background-color: rgba(0,0,255,.1)">Height 75%</div>
  <div class="h-100 d-inline-block" style="width: 120px; background-color: rgba(0,0,255,.1)">Height 100%</div>
  <div class="h-auto d-inline-block" style="width: 120px; background-color: rgba(0,0,255,.1)">Height auto</div>
</div>

You can also use max-width: 100%; and max-height: 100%; utilities as needed.

PlaceholderMax-width 100%
<svg class="docs-placeholder-img mw-100" width="100%" height="100" xmlns="http://www.w3.org/2000/svg" role="img" aria-label="Placeholder: Max-width 100%" preserveAspectRatio="xMidYMid slice" focusable="false"><title>Placeholder</title><rect width="100%" height="100%" fill="#868e96"/><text x="50%" y="50%" fill="#dee2e6" dy=".3em">Max-width 100%</text></svg>
Max-height 100%
<div style="height: 100px; background-color: rgba(255,0,0,.1);">
  <div class="mh-100" style="width: 100px; height: 200px; background-color: rgba(0,0,255,.1);">Max-height 100%</div>
</div>

Relative to the viewport

You can also use utilities to set the width and height relative to the viewport.

<div class="min-vw-100">Min-width 100vw</div>
<div class="min-vh-100">Min-height 100vh</div>
<div class="vw-100">Width 100vw</div>
<div class="vh-100">Height 100vh</div>

Sass

Utilities API

Sizing utilities are declared in our utilities API in scss/_utilities.scss. Learn how to use the utilities API.

    "width": (
      property: width,
      class: w,
      values: (
        25: 25%,
        50: 50%,
        75: 75%,
        100: 100%,
        auto: auto
      )
    ),
    "max-width": (
      property: max-width,
      class: mw,
      values: (100: 100%)
    ),
    "viewport-width": (
      property: width,
      class: vw,
      values: (100: 100vw)
    ),
    "min-viewport-width": (
      property: min-width,
      class: min-vw,
      values: (100: 100vw)
    ),
    "height": (
      property: height,
      class: h,
      values: (
        25: 25%,
        50: 50%,
        75: 75%,
        100: 100%,
        auto: auto
      )
    ),
    "max-height": (
      property: max-height,
      class: mh,
      values: (100: 100%)
    ),
    "viewport-height": (
      property: height,
      class: vh,
      values: (100: 100vh)
    ),
    "min-viewport-height": (
      property: min-height,
      class: min-vh,
      values: (100: 100vh)
    ),