ProductSolutionsTemplatesResources

ISOWEEKNUM

Returns the number of the ISO week of the year where the provided date falls. Learn more

Video field
Date

ISOWEEKNUM is a function used in spreadsheet software, such as Microsoft Excel or Google Sheets, that returns the ISO week number for a given date.

The ISO week numbering system is a standard way of representing weeks in the calendar year, which is used internationally. It defines a week as starting on Monday and ending on Sunday, and the week number is determined by the number of Thursdays in a year that occur before that week.

For example, the first week of the year is the week that contains the first Thursday of the year, and it is assigned the week number 1. ISOWEEKNUM(date) returns a number between 1 and 53, representing the ISO week number for the specified date.

Visit Official Docs

Want even more from Google Sheets?


With Softr, you can turn your spreadsheets into powerful web apps.You can give advanced roles and permissions to each user, build advanced logic and automation flows, customize the design to your needs, and much more.


Softr also offers a growing library of templates for internal tools, client portals, community hubs, and more. The templates come with a Google Sheet or an Airtable base that you can use to store and manage your data easily.


Try Softr now and build your custom web apps in 10 minutes – no code required!