microsoft.excel.training - Countif

CountIf works on the basis that if any value in the range you select meets your criteria, then it will be added to the count.

COUNTIF(range,criteria)

Range:
is the range of cells from which you want to count cells.

Criteria:
is the criteria in the form of a number, expression, cell reference, or text that defines which cells will be counted. For example, criteria can be expressed as 32, "32", ">32", "apples", or B4.