COUNTVISIBLE

COUNTVISIBLE(rgeValues)
Returns the number of visible non blank cells.

REMARKS
* This function excludes hidden cells.
* You can use the built-in COUNT function to include hidden cells.
* You can use the user defined COUNTAVISIBLE function to
* You can use the user defined COUNTVISIBLEIFS function to
* Similar to the user defined functions AVERAGEVISIBLE, MAXVISIBLE, MEDIANVISIBLE, MINVISIBLE and SUMVISIBLE
* You could also use aggregate(2,5,range)
Public Function COUNTVISIBLE( _

Public Function COUNTVISIBLE( _ 
         ByVal rgeValues As Range) _ 
         As Integer 

Dim rgeCell As Range 
Dim itotalcells As Integer 

   Application.Volatile 
   
   For Each rgeCell In rgeValues 
   
      If (rgeCell.EntireRow.Hidden = False) And _ 
         (rgeCell.EntireColumn.Hidden = False) Then 
         
         itotalcells = itotalcells + 1 
      End If 

   Next rgeCell 
   
   COUNTVISIBLE = itotalcells 
End Function 

For instructions on how to add this function to a workbook refer to the page under Inserting Functions