# How to Count Cells on A Day of A Month

The SUMPRODUCT function is to return the sum of the products of corresponding ranges or arrays. It can also count the cells in a certain yeara month, or a day. It can also count the cells in a month and day, e.g., a person's birthday on June 22.

Example: You are working with a dataset with the first name in column A, the last name in column B, and the DOB (date of birth) in column C.

Formula 1: To count the number of people that were born on June 22

=SUMPRODUCT(--(MONTH(C2:C12)=6), --(DAY(C2:C12)=22))

• (MONTH(C2:C12)=6): if DOB is in June, it returns true, otherwise false;
• ( DAY(C2:C12)=22): if DOB is on 22, it returns true, otherwise false;
• The double hyphens (--) convert true into 1, and false into 0;
• The SUMPRODUCT returns the sum of the products of the array.

The result returns 3, and three people were born on June 22.

Formula 2: To count the number of people that were born on November 21

=SUMPRODUCT(--(MONTH(C2:C12)=11), --(DAY(C2:C12)=21))

The result returns 2, and two people were born on November 21

Notes: The SUMPRODUCT function

The SUMPRODUCT function adds all the multiplication results for all arrays.

Formula:

=SUMPRODUCT(array1, [array2], …)

Explanations:

– Array1 is required, the first array is to multiply and then add.
– Array2 is optional, the second array is to multiply and then add.