Skip to content
Free Excel Tutorials
  • Home
  • Excel For Beginners
  • Excel Intermediate
  • Advanced Excel For Experts

Data Analysis

  • Add Outline to Data in Excel
  • Randomize/ Shuffle List in Excel
  • Data Series in Excel
  • How to create Checklist in Excel
  • How to calculate correlation coefficient Correlation in Excel

References

  • How to calculate two-way lookup VLOOKUP in Excel Table
  • How to use Excel ROW Function
  • Excel Advanced Lookup using Index and Match Functions
  • Offset in Excel
  • CHOOSE function: Description, Usage, Syntax, Examples and Explanation

Data Validations

  • Excel Data validation whole percentage only
  • Excel Data validation only dates between
  • How To Create Drop-down List in Excel
  • Excel Data validation allow weekday only
  • Excel Data validation must begin with

ISOWEEKNUM function: Description, Usage, Syntax, Examples and Explanation

by

What is ISOWEEKNUM function in Excel?

ISOWEEKNUM function is one of Date and Time functions in Microsoft Excel that returns number of the ISO week number of the year for a given date.

Syntax of ISOWEEKNUM function

ISOWEEKNUM(date)

The ISOWEEKNUM function syntax has the following arguments.

  • Date: Date is the date-time code used by Excel for date and time calculation.

ISOWEEKNUM formula explanation

  • Microsoft Excel stores dates as sequential numbers so they can be used in calculations. By default, January 1, 1900 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39,448 days after January 1, 1900.
  • If the date argument is not a valid number, ISOWEEKNUM returns the #NUM! error value.
  • If the date argument is not a valid date type, ISOWEEKNUM returns the #VALUE! error value.

Example of ISOWEEKNUM function

Steps to follow:

1. Open a new Excel worksheet.

2. Copy data in the following table below and paste it in cell A1

Note: For formulas to show results, select them, press F2 key on your keyboard and then press Enter.

You can adjust the column widths to see all the data, if need be.

Date
3/9/2012
Formula Description Result
=ISOWEEKNUM(A2) Number of the week in the year that 3/9/2012 occurs, based on weeks beginning on the default, Monday (10). 10

Post navigation

Previous Post:

How to generate random date between two dates in Excel

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Learn Basic Excel

Ribbon
Workbook
Worksheets
Format Cells
Find & Select
Sort & Filter
Templates
Print
Share
Protect
Keyboard Shortcuts

Categories

  • Charts
  • Data Analysis
  • Data Validation
  • Excel Functions
    • Cube Functions
    • Database Functions
    • Date and Time Functions
    • Engineering Functions
    • Financial Functions
    • Information Functions
    • Logical Functions
    • Lookup and Reference Functions
    • Math and Trig Functions
    • Statistical Functions
    • Text Functions
    • Web Functions
  • Excel VBA
  • Excel Video Tutorials
  • Formatting
  • Grouping
  • Others

Logical Functions

  • How to use Excel NOT Function
  • AND function: Description, Usage, Syntax, Examples and Explanation
  • FALSE function: Description, Usage, Syntax, Examples and Explanation
  • How to use IFS function in Excel
  • How to use Excel TRUE Function

Date Time

  • Custom weekday abbreviation in Excel
  • Add business days to date in Excel
  • How to calculate months between dates in Excel
  • Get days between dates in Excel
  • WEEKNUM function: Description, Usage, Syntax, Examples and Explanation

Grouping

  • Group times into unequal buckets in Excel
  • Running count group by n size in Excel
  • Group numbers at uneven intervals in Excel
  • How to randomly assign data to groups in Excel
  • If cell contains one of many things in Excel

General

  • Transpose: Switch ‘Rows to Columns’ or ‘Columns to Rows’ in Excel
  • How to calculate profit margin percentage in Excel
  • Lock Cells in a Worksheet Excel
  • Advanced Number Formats in Excel
  • How to fill cell ranges with random number from fixed set of options in Excel
© 2026 xlsoffice . All Right Reserved. | Teal Smiles | Abbreviations And Their Meaning