=COUNTIF(rng,"<>X")

If you need to count the number of cells that contain values not equal to a particular value, you can use the COUNTIF function. In the generic form of the formula (above) rng represents a range of cells, and X represents the value you don't want to count. All other values will be counted.

In the example, the active cell contains this formula:

=COUNTIF(D4:D10,"<>Complete")

COUNTIF counts the number of cells in the range that meet criteria you supply.

In the example, we use "<>" (the logical operator for "does not equal") to count cells in the range D4:D10 that don't equal "complete". COUNTIF returns the count as a result.

COUNTIF is __not__ case-sensitive. In this example, the word "complete" can appear in any combination of uppercase / lowercase letters and will not be counted.

If you want to use a value in another cell as part of the criteria, use the ampersand (&) character to concatenate like this:

=COUNTIF(rng,"<>"&a1)

If the value in cell a1 is "100", the criteria will be "<>100" after concatenation, and COUNTIF will count cells not equal to 100.