How to get dynamic data-offset values for Bootstrap 3 affix method

You could use jQuery to get the dynamic content height above the navbar. For example:

$('#nav').affix({
      offset: {
        top: $('header').height()
      }
}); 

Working demo: http://bootply.com/69848

In some cases, offset.bottom must also be calculated to determine when to “un-affix” the element. Here’s an example of affix-bottom