Bootstrap 4
Bootstrap 4 Badges
To create a bootstrap 4 badge, apply the .badge class, as well as one of the .badge-primary, .badge-secondary, .badge-success, .badge-danger, .badge-warning, .badge-info, .badge-light, .badge-dark  classes to the <span> element that represents the badge.
<h1>Example heading <span class="badge badge-secondary">New</span></h1>
<h2>Example heading <span class="badge badge-secondary">New</span></h2>
<h3>Example heading <span class="badge badge-secondary">New</span></h3>
<h4>Example heading <span class="badge badge-secondary">New</span></h4>
<h5>Example heading <span class="badge badge-secondary">New</span></h5>
<h6>Example heading <span class="badge badge-secondary">New</span></h6>
Output :
Button Badges

Badges can be used as part of links or buttons to provide a counter.

<button type="button" class="btn btn-primary">
  Tutorials <span class="badge badge-light">14</span>
Output :
Contextual Badges

The contextual classes (.badge-*) to change the color of a badge.

<span class="badge badge-default">Default</span>
<span class="badge badge-primary">Primary</span>
<span class="badge badge-secondary">Secondary</span>
<span class="badge badge-success">Success</span>
<span class="badge badge-danger">Danger</span>
<span class="badge badge-warning">Warning</span>
<span class="badge badge-info">Info</span>
<span class="badge badge-light">Light</span>
<span class="badge badge-dark">Dark</span>
Output :
Pill Badges

Use the bootstrap 4 pill badges are add .badge-pill class to make the badges more round.

<span class="badge badge-pill badge-default">Default</span>
<span class="badge badge-pill badge-primary">Primary</span>
<span class="badge badge-pill badge-secondary">Secondary</span>
<span class="badge badge-pill badge-success">Success</span>
<span class="badge badge-pill badge-danger">Danger</span>
<span class="badge badge-pill badge-warning">Warning</span>
<span class="badge badge-pill badge-info">Info</span>
<span class="badge badge-pill badge-light">Light</span>
<span class="badge badge-pill badge-dark">Dark</span>
Output :