How can i get default font size in pixels by using JavaScript or JQuery?

Question

As you know em is a relative font measurement where one em is equal to the height of the letter \"M\" in the default font size. An advantage in using it is because you will be a

Answer 1

There are a couple of situations this can be useful-

function getDefaultFontSize(pa){
 pa= pa || document.body;
 var who= document.createElement('div');

 who.style.cssText='display:inline-block; padding:0; line-height:1; position:absolute; visibility:hidden; font-size:1em';

 who.appendChild(document.createTextNode('M'));
 pa.appendChild(who);
 var fs= [who.offsetWidth, who.offsetHeight];
 pa.removeChild(who);
 return fs;
}

alert(getDefaultFontSize())