{"id":278,"date":"2025-07-15T13:34:46","date_gmt":"2025-07-15T13:34:46","guid":{"rendered":"https:\/\/functiontranslator.com\/2021\/02\/12\/isoweeknum\/"},"modified":"2021-02-13T11:34:51","modified_gmt":"2021-02-13T11:34:51","slug":"isoweeknum","status":"publish","type":"post","link":"https:\/\/functiontranslator.com\/en\/isoweeknum\/","title":{"rendered":"ISOWEEKNUM"},"content":{"rendered":"

Below is a comprehensive guide on utilizing the ISOWEEKNUM function within Microsoft Excel and Google Sheets.<\/p>\n

Introduction to the ISOWEEKNUM Function<\/h2>\n

The ISOWEEKNUM function determines the ISO week number of the year for any given date. According to the ISO system, week numbers range from 1 to 53. The first week of the year (Week 1) is defined as the week containing the first Thursday of that year.<\/p>\n

Syntax<\/h2>\n

The syntax for using the ISOWEEKNUM function is consistent across both Microsoft Excel and Google Sheets:<\/p>\n

ISOWEEKNUM(date)<\/code><\/pre>\n
Here, date<\/code> refers to the date you wish to evaluate for its ISO week number.<\/p>\n
Examples<\/h2>\n
Example 1: Basic Usage<\/h3>\n
Suppose cell A1 has the date “2022-09-15”. To determine the ISO week number for this date, you would use the following formula:<\/p>\n\n\n\n
Date<\/strong><\/td>\nFormula<\/strong><\/td>\nISOWEEKNUM Result<\/strong><\/td>\n<\/tr>\n
2022-09-15<\/td>\n=ISOWEEKNUM(A1)<\/td>\n37<\/td>\n<\/tr>\n<\/table>\n
Example 2: Applying ISOWEEKNUM in Google Sheets<\/h3>\n
The application in Google Sheets mirrors that of Excel. For a date entered in cell A1, the formula to find its ISO week number is:<\/p>\n
=ISOWEEKNUM(A1)<\/code><\/pre>\n
Use Cases<\/h2>\n
    \n
  • Tracking project timelines by referencing ISO week numbers.<\/li>\n
  • Organizing work schedules or events utilizing ISO week number categorization.<\/li>\n
  • Deriving week-based metrics or Key Performance Indicators (KPIs) for comprehensive business analysis.<\/li>\n<\/ul>\n
    Employing the ISOWEEKNUM function allows for seamless integration of ISO week numbers into your date-centric calculations and analyses in both Excel and Google Sheets.<\/p>\n","protected":false},"excerpt":{"rendered":"
    Returns the number of the ISO week number of the year for a given date<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[209],"tags":[],"class_list":["post-278","post","type-post","status-publish","format-standard","hentry","category-date-and-time"],"acf":[],"yoast_head":"\nExcel ISOWEEKNUM Function \u2013 How It Works, Formula Examples and Syntax<\/title>\n<meta name=\"description\" content=\"Learn what the Excel ISOWEEKNUM function does. 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