jquery selector to count the number of visible table rows?

You can use the :visible selector and .length like this:

var numOfVisibleRows = $('tr:visible').length;

If the <table> itself isn't visible on the screen (:visible returns false if any parent is hidden, the element doesn't have to be hidden directly), then use .filter(), like this:

var numOfVisibleRows = $('tr').filter(function() {
  return $(this).css('display') !== 'none';
}).length;

$('tr:visible').length

You can also view particular table visible rows

 var totalRow =  $('#tableID tr:visible').length;
 var totalRowWithoutHeader = totalRow-1;

The totalRowWithoutHeader gives the total row count excluding header row.

$("tr:visible") gets you the results of the visible rows, and I think you can then do .length