Returns the week number of a specific date within a year.
Cú pháp
WEEKNUM(serial_number, [return_type])Đối số
serial_numberbắt buộc
The date to evaluate, represented as a serial number or date string.
return_typetùy chọn
A number determining which day the week begins on (default is 1 for Sunday).
The WEEKNUM function calculates the ordinal number of the week for a given date. It identifies which week of the year the date falls into, with the week containing January 1st being considered the first week.
=WEEKNUM("2023-01-15")→3Returns the week number for January 15, 2023, assuming the week starts on Sunday.
Select the cell
Click the cell where you want to display the week number.
Enter the formula
Type =WEEKNUM( and select the cell containing the date, then close the parenthesis.
No, use the ISOWEEKNUM function if you need to follow the ISO 8601 standard.