Grid options

While Bootstrap uses ems or rems for defining most sizes, pxs are used for grid breakpoints and container widths. This is because the viewport width is in pixels and does not change with the font size.

See how aspects of the Bootstrap grid system work across multiple devices with a handy table.

Extra small
<576px
Small
≥576px
Medium
≥768px
Large
≥992px
Extra large
≥1200px
Max container widthNone (auto)540px720px960px1140px
Class prefix.col-.col-sm-.col-md-.col-lg-.col-xl-
# of columns12
Gutter width30px (15px on each side of a column)
NestableYes
Column orderingYes
Online Customers
pending Task