Responsive images

Images in Bootstrap are made responsive with .img-fluid. This applies max-width: 100%; and height: auto; to the image so that it scales with the parent element.

<img src="..." class="img-fluid" alt="...">

Image thumbnails

In addition to our border-radius utilities, you can use .img-thumbnail to give an image a rounded 1px border appearance.

<img src="..." class="img-thumbnail" alt="...">

Aligning images

Align images with the helper float classes or text alignment classes. block-level images can be centered using the .mx-auto margin utility class.

<img src="..." class="rounded float-start" alt="...">
<img src="..." class="rounded float-end" alt="...">

<img src="..." class="rounded mx-auto d-block" alt="...">

<div class="text-center">
  <img src="..." class="rounded" alt="...">
</div>

Picture

If you are using the <picture> element to specify multiple <source> elements for a specific <img>, make sure to add the .img-* classes to the <img> and not to the <picture> tag.

​<picture>
  <source srcset="..." type="image/svg+xml">
  <img src="..." class="img-fluid img-thumbnail" alt="...">
</picture>

Sass

Variables

Variables are available for image thumbnails.

$thumbnail-padding:                 .25rem;
$thumbnail-bg:                      $body-bg;
$thumbnail-border-width:            $border-width;
$thumbnail-border-color:            $gray-300;
$thumbnail-border-radius:           $border-radius;
$thumbnail-box-shadow:              $box-shadow-sm;