If you want to count the total characters in a range of cells, you can do with a formula that uses LEN, along with the SUMPRODUCT function.
Formula
=SUMPRODUCT(LEN(rng))
Explanation
In the example, the active cell contains this formula:
=SUMPRODUCT(LEN(B3:B6))
Here’s how the formula works:
SUMPRODUCT accepts the range B3:B6 as an array of four cells. For each cell in the array, LEN calculates the length of the text as a number. The result is an array that contains 4 numbers. SUMPRODUCT then sums the items in this array and returns the total.