Spinners

Border spinner
<div class="spinner-border text-primary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-secondary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-success" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-danger" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-warning" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-info" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-light" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-dark" role="status">
  <span class="sr-only">Loading...</span>
</div>
Growing spinner
<div class="spinner-grow text-primary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-secondary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-success" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-danger" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-warning" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-info" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-light" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-grow text-dark" role="status">
  <span class="sr-only">Loading...</span>
</div>
Alignment
Loading... 
<div class="spinner-border" role="status">
  <span class="sr-only">Loading...</span>
</div>

<div class="d-flex justify-content-center">
  <div class="spinner-border" role="status">
    <span class="sr-only">Loading...</span>
  </div>
</div>

<div class="clearfix">
  <div class="spinner-border float-right" role="status">
    <span class="sr-only">Loading...</span>
  </div>
</div>

<div class="d-flex align-items-center">
  <strong>Loading...</strong>
  <div class="spinner-border ml-auto" role="status" aria-hidden="true"></div>
</div>
Size
<!-- sm -->
<div class="spinner-border spinner-border-sm" role="status">
  <span class="sr-only">Loading...</span>
</div>

<!-- lg -->
<div class="spinner-border" style="width: 3rem; height: 3rem;" role="status">
  <span class="sr-only">Loading...</span>
</div>
Buttons
<button class="btn btn-primary" type="button" disabled>
  <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
  <span class="sr-only">Loading...</span>
</button>

<button class="btn btn-primary" type="button" disabled>
  <span class="spinner-border spinner-border-sm mr-2" role="status" aria-hidden="true"></span>
  Loading...
</button>