Wonky bor, you certain you ain't altering the diagram, just found 2 more making it now 48!!! Final offer take it or leave it.
I make it 40, too - 16 + the 2 hovering squares, the 8 inside those 2 hovering squares, by quartering the outside square, and gradually moving round you find 8 more + the quarter in the very middle, which so far makes 35, then there are 4 3x3 squares + the very outside one = 40
RBF bor, I miscalculated on the 3x3s, should be 4 not 8. 1 large square 8 smallest squares 4 3x3s 18 1x1s 9 2x2s Total 40 squares. RBF bor, I bow to your calculating genius LOL.
40. Without the 2 tricky ones it is the standard square number addition 1+4+9+16 = 30 then 2 bigguns and 8 small uns
I'm sorry, its official, there are 40. I found 36 but I googled it and its 40. Sorry to spoil the fun, Next!
Thanks for ruining the fun redruth... . That's cheating. Answer is 40. 16 squares, 2 smaller off centre squares, these squares divided into 8, 1 big square, 4 lots of 3x3 squares, 9 lots of 2x2 squares.