i\'m having this html structure:
Content goes here
Use $("div.content").outerHeight();
instead.
If you add -true- in the parenthesis if you want to include all margins & paddings as well.
$('div.content').outerHeight(true);
Also cross-browser heights may differ if you don't have very good CSS Resets, or are looking at a legacy browser (ie6/7), but with a good reset their differences will be very miniscule.
jsFiddle Demo