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

Data Analysis

  • How To Load Analysis ToolPak in Excel
  • Conditional Formatting Data bars Examples in Excel
  • How to create a Histogram in Excel
  • Chart Axes in Excel
  • Calculate Conditional Percentile ‘IF’ in table in Excel

References

  • To count total rows in a range in Excel
  • How to use Excel ROW Function
  • Convert text string to valid reference in Excel using Indirect function
  • How to get last row in text data in Excel
  • How to use Excel MATCH Function

Data Validations

  • Excel Data validation no punctuation
  • Excel Data validation only dates between
  • Excel Data validation must begin with
  • Excel Data validation unique values only
  • Excel Data validation require unique number

How to calculate project start date based on end date in Excel

by

To calculate a project start date or custom date based on an end date and duration in days, you can use the WORKDAY function.

Note: WORKDAY function does not count the start date as a workday.

Formula

=WORKDAY(start,-days,holidays)

Explanation

In the example shown, the formula in E5 is:

=WORKDAY(C5,-D5,holidays)

where “holidays” is the named range G5:G9.

How this formula works

This formula is uses the WORKDAY function, which returns a date in the future or past, based on start date and required work days. WORKDAY automatically excludes weekends, and can also exclude holidays if provided as a range of dates.

In the example shown, the project end date is in column C, and days is in column D. The end date represents a due date or target date, and days represents duration in work days. In column E, the WORKDAY function calculates a date by which the project must start in order to finish by the end date.

In this case, we need to count backwards from the end date, so we supply days as a negative number. For holidays, we provide the named range”holidays”, which includes the dates in G5:G9. The dates will not be included as workdays.

With a negative value for days, WORKDAY moves in time from the end date, taking into account weekends and holidays, and returns December 19, 2018 as the start date. If holidays are not provided, the same formula returns a start date of December 24.

Custom workdays

If your schedule requires custom workdays (i.e. weekdays are not Monday-Friday) you can substitute the WORKDAY.INTL function for WORKDAY. For example, to calculate a start date for a project where workdays include Saturday, you could use:

=WORKDAY.INTL(C5,-D5,11,holidays)

WORKDAY.INTL can be configured in many ways.

Post navigation

Previous Post:

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

Next Post:

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

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 IFS function in Excel
  • Complete List of Excel Logical Functions, References and Examples
  • Return blank if in Excel
  • TRUE function: Description, Usage, Syntax, Examples and Explanation
  • SWITCH function example in Excel

Date Time

  • How to calculate nth day of week in month in Excel
  • Add decimal hours to time in Excel
  • How to calculate next day of week in Excel
  • How to join date and text together in Excel
  • Add workdays to date custom weekends in Excel

Grouping

  • Group arbitrary text values in Excel
  • How to randomly assign people to groups in Excel
  • Group times into unequal buckets in Excel
  • If cell contains one of many things in Excel
  • Running count group by n size in Excel

General

  • Excel Autofill Cell Ranges, Copy, Paste
  • Transpose: Switch ‘Rows to Columns’ or ‘Columns to Rows’ in Excel
  • Automatically fill series of cells in Excel using AutoFill
  • How to calculate total from percentage in Excel
  • Split Cell Content Using Text to Columns in Excel
© 2025 xlsoffice . All Right Reserved. | Teal Smiles | Abbreviations And Their Meaning