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

Data Analysis

  • How to calculate average last N values in a table in Excel
  • How To Sort One Column or Multiple Columns in Excel
  • Add Outline to Data in Excel
  • How To Perform and Interpret Regression Analysis in Excel
  • How to count table rows in Excel

References

  • To count total rows in a range in Excel
  • VLOOKUP function: Description, Usage, Syntax, Examples and Explanation
  • Extract all partial matches in Excel
  • How to get last row in numeric data in Excel
  • LOOKUP function: Description, Usage, Syntax, Examples and Explanation

Data Validations

  • Excel Data validation number multiple 100
  • Excel Data validation whole percentage only
  • Excel Data validation with conditional list
  • How To Create Drop-down List in Excel
  • Excel Data validation require unique number

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Your email address will not be published.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

  • Complete List of Excel Logical Functions, References and Examples
  • IFERROR function: Description, Usage, Syntax, Examples and Explanation
  • Return blank if in Excel
  • IF, AND, OR and NOT Functions Examples in Excel
  • Invoice status with nested if in Excel

Date Time

  • Get project end date in Excel
  • Get days, months, and years between dates in Excel
  • YEARFRAC function: Description, Usage, Syntax, Examples and Explanation
  • Next biweekly payday from date in Excel
  • NOW function: Description, Usage, Syntax, Examples and Explanation

Grouping

  • How to randomly assign data to groups in Excel
  • Group numbers at uneven intervals in Excel
  • How to randomly assign people to groups in Excel
  • Categorize text with keywords in Excel
  • Group numbers with VLOOKUP in Excel

General

  • Cell References: Relative, Absolute and Mixed Referencing Examples
  • How to Insert Cells, Row and Rows in Excel
  • How to choose page/paper size in Excel before Printing
  • 231 Keyboard Shortcut Keys In Excel
  • Excel Operators
© 2025 xlsoffice . All Right Reserved. | Teal Smiles | Abbreviations And Their Meaning