This puzzle contains more than the 16 small squares visible at first glance. To find the full total, count squares of every possible size.
There are:
16 squares measuring 1 × 1
9 squares measuring 2 × 2
4 squares measuring 3 × 3
1 large square measuring 4 × 4
Now add them together:
16 + 9 + 4 + 1 = 30
Answer: 30 squares.


