bootstrap div vertical center

1<div class="d-flex align-items-start">...</div>
2<div class="d-flex align-items-end">...</div>
3<div class="d-flex align-items-center">...</div>
4<div class="d-flex align-items-baseline">...</div>
5<div class="d-flex align-items-stretch">...</div>

1<!-- Center columns in a Row -->
2<div class="row d-flex justify-content-center text-center">
3    <div class="col-4">
4        // Add Content
5    </div>
6    <div class="col-4">
7        // Add Content
8    </div>
9    <div class="col-4">
10        // Add Content
11    </div>
12</div>

1<div class="jumbotron d-flex align-items-center min-vh-100">
2  <div class="container text-center">
3    I am centered vertically
4  </div>
5</div>
6

1mx-auto mt-auto mb-auto

1<div class="container h-100">
2    <div class="row align-items-center h-100">
3        <div class="col-6 mx-auto">
4            <div class="jumbotron">
5                I'm vertically centered
6            </div>
7        </div>
8    </div>
9</div>
10

1<div class="my-auto">
2  ...inner divs and content...
3</div>