Very different font sizes across browsers

Question

Update: Added simple test example http://jsfiddle.net/7UhrW/1/ using normalize.css.

Chrome/WebKit and Firefox have different rendering engines which

Answer 1

Use Font-sites in pt instead like font-size:12pt

Answer 2

Use unitless line-height for BODY (or HTML) element:

BODY {line-height: 1.25; }