Source

images

Documentation and examples for opting images into responsive behavior (so they never become larger than their parent elements) and add lightweight styles to them—all via classes.

Responsive images

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

Placeholder Responsive image 
<img src="..." class="img-fluid" alt="Responsive image">
SVG images and IE 10

In Internet Explorer 10, SVG images with .img-fluidare disproportionately sized. To fix this, add width: 100% \9;where necessary. This fix improperly sizes other image formats, so Bootstrap doesn't apply it automatically.

Image thumbnails

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

A generic square placeholder image with a white border around it, making it resemble a photograph taken with an old instant camera 200x200 
<img src="..." alt="..." class="img-thumbnail">

Aligning images

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

Placeholder 200x200 Placeholder 200x200 
<img src="..." class="rounded float-left" alt="...">
<img src="..." class="rounded float-right" alt="...">
Placeholder 200x200 
<img src="..." class="rounded mx-auto d-block" alt="...">
Placeholder 200x200 
<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>