Tamaño del icono de control HTML
you can change the size of an icon using the font size rather than setting the height and width of an icon. Here is how you do it:
<i class="fa fa-minus-square-o" style="font-size: 0.73em;"></i>
There are 4 ways to specify the dimensions of the icon.
px : give fixed pixels to your icon
em : dimensions with respect to your current font. Say ur current font is 12px then 1.5em will be 18px (12px + 6px).
pt : stands for points. Mostly used in print media
% : percentage. Refers to the size of the icon based on its original size.
Eminem The Programmer