The counta() functions will tell you how many non-blank entries are in a group of cells.
I actually had an occasion to use counta() earlier this week. I had a sort of to-do list in one column, and notes about how I’d addressed each one in another column. The thing is, to-do lists tend to grow, so counta() was perfect for telling me how many items were currently in the list.
Since what’s important is not only how many tasks are in the list, but how many are left, I also used counta() on the column with notes. That told me how many I’d done (always a good motivator!), and by subtracting that from the total number of tasks I could find out how many were left.
Like count(), counta() can accept more than one range if they’re separated by commas. You could count all the entries in column A and all the entries in column B in the same function, counta(A:A,B:B). It’s worth noting, however, that if two ranges overlap, then you’ll be counting any entries in the overlapping section twice. For example, if you counted all the entries in column A, and all the numbers in row 1 with counta(A:A,1:1), then if cell A1 had anything in it then your result would have one more number than is actually there.
Pretty much everything can count as an entry, depending on which program you’re using. If there is absolutely anything in the cell, it could count. Even a formula that appears blank when you look at the cell, such as =’ or =concatenate(“”), could count as an entry. I recommend experimenting with your program and some known values before assuming it one way or another.