mdennis-vpm

Bootstrap 4 Default breakpoints (and corresponding fixed-width container sizes):
* xs = 575px and below (100% container, with 15px default left and right paddings)
* sm = 576px – 767px  (540px container, with default paddings)
* md = 768px – 991px (720px container, with default paddings)
* lg = 992px – 1199px (960px container, with default paddings)
* xl = 1200px and up (1140px container, with default paddings)

“Container” dimensions are for when non-fluid containers are used. 
I personally prefer working with non-fluid containers, 
as it leads to massively reduced probability of layout issues.