The best answer to what you want is
echo `find . -maxdepth 1 -type d | wc -l`-1 | bc
this subtracts one to remove the unwanted '.' directory that find lists (as patel deven mentioned above).
If you want to count subfolders recursively, then just leave off the maxdepth option, so
echo `find . -type d | wc -l`-1 | bc
PS If you find command substitution ugly, subtracting one can be done as a pure stream using sed
and bc
.
Subtracting one from count:
find . -maxdepth 1 -type d | wc -l | sed 's/$/-1\n/' | bc
or, adding count to minus one:
find . -maxdepth 1 -type d | wc -l | sed 's/^/-1+/' | bc