Formulas > =WEEKNUM()

How To Use WEEKNUM() Function in Google Sheets


Returns a number representing the week of the year where the provided date falls.

Common questions about the WEEKNUM formula include:
- How do I enter a WEEKNUM formula into Google Sheets?
- What is the syntax of a WEEKNUM formula?
- What values can the WEEKNUM formula accept? 

The WEEKNUM formula can be used to calculate the week number of a given date (or cell value with a date). It can also be used to determine how many weeks have past between two designated dates.

The WEEKNUM formula can be commonly mistyped as WEEKNM, WEEKNOM, or even WAMNUM.

Some common ways the WEEKNUM formula is used inappropriately are: using it to calculate the day of the week from a given date, or attempting to calculate a duration between dates without using the correct syntax.

Common pitfalls when using the WEEKNUM formula include forgetting to specify the start of the week (Sunday or Monday). When a start is not indicated, the return value of the WEEKNUM formula is unpredictable.

Common mistakes when using the WEEKNUM Formula include mistakenly specifying the start of the week when calculating a duration between dates. The start of the week should only be indicated when calculating the week number of a given date.

Common misconceptions people might have with the WEEKNUM Formula include thinking that the WEEKNUM formula can also calculate month numbers or quarter numbers, which it cannot. They may also think that the WEEKNUM formula automatically assumes Sunday as its baseline, when this must be specified.

How To Actually Use WEEKNUM() in Sheets

WEEKNUM(date, [type])

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