Bootstrap: How to center content vertically within a column

You can use flexbox. Make your outer div, display: flex and use The property align-items to make it's contents vertically center. Here is the code:

#outerDiv{
    display: flex;
    align-items: center;
    flex-wrap: wrap;
}

In Bootstrap 4, add "align-self-center"-class to the col, where you want the content centred vertically.