Microsoft Excel Training Videos

COUNTIF function in Excel

The COUNTIF function in Excel counts the number of cells within a range that meet a given criteria
Range is the range of cells from which you want to count cells.
Criteria is the criteria or condition 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 200, "200", ">9000", "yes", or a4 in Excel.

You can use the wildcard characters, question mark (?) and asterisk (*), in criteria. A question mark matches any single character; an asterisk matches any sequence of characters. If you want to find an actual question mark or asterisk, type a tilde (~) before the character.

Microsoft Excel provides additional functions that can be used to analyze your data based on a condition.
To calculate a sum based on a string of text or a number within a range, use the SUMIF worksheet function.
To have a formula return one of two values based on a condition, such as a sales bonus based on a specified sales amount, use the IF worksheet function.
To count cells that are empty or not empty, use the COUNTA and COUNTBLANK functions.

Further reading on the countif function in Excel
Countif Function
Count cells that match criteria -- Countif Function

COUNTIF function in Excel