Images

Use bootstrap classes for opting images into responsive behavior.

Responsive images

Make images responsive with .img-fluid which applies max-width: 100%; and height: auto; to the image so that it scales with the parent element.

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

Image thumbnails

Use .img-thumbnail in addition to border-radius utilities to give an image a rounded 1px border appearance.

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-left" alt="...">
<img src="..." class="rounded float-right" alt="...">

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

Picture

When using the <picture> element to specify multiple <source> elements for a specific <img>, 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>