Where i can view The total rows / per board

Is there a way to be informed about the rows capacity i am currently using per board without the need to export the data to excel ?

The quick and dirty method is to use Ctrl+A to select every row in every group on the board, and the group action popup at the bottom of the screen will helpfully tell you how many rows you’ve got in total. You can do a similar thing group-by-group if you use ‘select all’ from the group dropdown menu.