# Sizing · Bootstrap
Easily make an element as wide or as tall (relative to its parent) with our width and height utilities.
Author: Mark Otto, Jacob Thornton, and Bootstrap contributors

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# Sizing

Easily make an element as wide or as tall (relative to its parent) with our width and height utilities.

Width and height utilities are generated from the `$sizes` Sass map in `_variables.scss`. Includes support for `25%`, `50%`, `75%`, and `100%` by default. Modify those values as you need to generate different utilities here.

Width 25%
Width 50%
Width 75%
Width 100%

    <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>

Height 25%
Height 50%
Height 75%
Height 100%

    <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>

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

    <img class="mw-100" src="..." alt="Max-width 100%">

Max-height 100%

    <div style="height: 100px; background-color: rgba(255,0,0,0.1);">
      <div class="mh-100" style="width: 100px; height: 200px; background-color: rgba(0,0,255,0.1);">Max-height 100%</div>
    </div>