How To Calculate Between Today And A Date In Excel

Calculate the exact difference between today and any date in Excel format. Get results in days, months, years, and more with visual chart representation.

Comprehensive Guide: How to Calculate Between Today and a Date in Excel

Calculating the difference between dates is one of the most common tasks in Excel, whether you’re tracking project deadlines, calculating ages, or analyzing time-based data. This comprehensive guide will walk you through all the methods, functions, and best practices for date calculations in Excel.

Understanding Excel Date Serial Numbers

Before diving into calculations, it’s crucial to understand how Excel stores dates:

• Excel stores dates as sequential serial numbers called date serial numbers
• January 1, 1900 is serial number 1 (Windows) or January 1, 1904 is serial number 0 (Mac)
• Time is stored as fractional portions of a 24-hour day (.5 = 12:00 PM)
• The maximum date Excel can handle is December 31, 9999 (serial number 2,958,465)

Official Microsoft Documentation

For complete technical specifications on Excel’s date-time system, refer to Microsoft’s official documentation: Date and Time Functions in Excel

Method 1: Using the DATEDIF Function (Most Versatile)

The DATEDIF function is Excel’s most powerful tool for date calculations, though it’s not officially documented in newer versions. It can calculate differences in days, months, or years.

Syntax:

=DATEDIF(start_date, end_date, unit)

Unit Options:

• “D” – Complete days between dates
• “M” – Complete months between dates
• “Y” – Complete years between dates
• “YM” – Months between dates after complete years
• “YD” – Days between dates after complete years
• “MD” – Days between dates after complete months

Examples:

Formula	Description	Example Result (for 5/15/2023 to today)
=DATEDIF(“5/15/2023″,TODAY(),”d”)	Total days between dates	245
=DATEDIF(“5/15/2023″,TODAY(),”m”)	Complete months between dates	8
=DATEDIF(“5/15/2023″,TODAY(),”y”)	Complete years between dates	0
=DATEDIF(“5/15/2023″,TODAY(),”ym”)	Months after complete years	8
=DATEDIF(“5/15/2023″,TODAY(),”yd”)	Days after complete years	245

Method 2: Simple Subtraction for Days

The simplest way to calculate days between dates is to subtract them directly:

=TODAY()-A1

Where A1 contains your target date. This returns the number of days between today and the target date.

Pros and Cons:

• Pros: Extremely simple, works in all Excel versions
• Cons: Only returns days, doesn’t account for years/months

Method 3: Using the DAYS Function (Excel 2013+)

The DAYS function provides a more readable alternative to simple subtraction:

=DAYS(TODAY(),A1)

Note the order of arguments is reversed compared to subtraction.

Method 4: Calculating Business Days with NETWORKDAYS

For business calculations that exclude weekends and holidays:

=NETWORKDAYS(A1,TODAY())

To exclude specific holidays:

=NETWORKDAYS(A1,TODAY(),HolidayRange)

Where HolidayRange is a range of cells containing holiday dates.

Function	Best For	Example	Returns
DATEDIF	Complete date breakdowns	=DATEDIF(“1/1/2020″,TODAY(),”y”)	Years between dates
DAYS	Simple day counts	=DAYS(TODAY(),”12/31/2023″)	Days until year end
TODAY()-date	Quick day calculations	=TODAY()-A1	Days between dates
NETWORKDAYS	Business day counts	=NETWORKDAYS(A1,TODAY())	Workdays between dates
YEARFRAC	Fractional year calculations	=YEARFRAC(“1/1/2023”,TODAY(),1)	Fraction of year passed

Advanced Techniques

Calculating Age in Years, Months, and Days

Combine multiple DATEDIF functions for complete age calculations:

=DATEDIF(A1,TODAY(),"y") & " years, " & DATEDIF(A1,TODAY(),"ym") & " months, " & DATEDIF(A1,TODAY(),"md") & " days"

Handling Time Components

To include time in your calculations:

=TODAY()+NOW()-TODAY()-A1

Where A1 contains both date and time.

Creating Dynamic Date Ranges

Use these formulas for common date ranges:

• Days until end of month: =EOMONTH(TODAY(),0)-TODAY()
• Days since start of year: =TODAY()-DATE(YEAR(TODAY()),1,1)
• Days until next Friday: =7-WEEKDAY(TODAY(),16)

Common Pitfalls and Solutions

Issue 1: Getting ###### Errors

Cause: Column isn’t wide enough to display the date or the result is negative.

Solution: Widen the column or use IF to handle negative values:

=IF(TODAY()-A1<0,"Future Date",TODAY()-A1)

Issue 2: Incorrect Leap Year Calculations

Cause: Some custom date functions don't account for leap years.

Solution: Always use built-in functions like DATEDIF or DAYS which handle leap years automatically.

Issue 3: Time Zone Differences

Cause: Excel doesn't store time zone information with dates.

Solution: Convert all dates to UTC or a single time zone before calculations.

Excel vs. Google Sheets Date Functions

While similar, there are key differences between Excel and Google Sheets date functions:

Feature	Excel	Google Sheets
Date Serial Origin	1/1/1900 (Windows) 1/1/1904 (Mac)	12/30/1899
DATEDIF Function	Undocumented but works	Officially documented
NETWORKDAYS	Requires holiday range	Can accept array literal
Time Zone Handling	No native support	Limited support via apps script
Maximum Date	12/31/9999	12/31/9999

Academic Research on Date Calculations

The University of Texas at Austin maintains excellent resources on date-time calculations in spreadsheets: Excel Date Functions Tutorial

Real-World Applications

Project Management

Calculate:

• Days remaining until deadline
• Project duration in workdays
• Milestone completion percentages

Human Resources

Track:

• Employee tenure
• Vacation accrual
• Probation periods

Financial Analysis

Calculate:

• Investment holding periods
• Loan durations
• Billing cycles

Best Practices for Date Calculations

1. Always use cell references: Avoid hardcoding dates in formulas
2. Document your formulas: Add comments explaining complex date calculations
3. Handle errors gracefully: Use IFERROR to manage potential errors
4. Consider time zones: Standardize on UTC for global applications
5. Test edge cases: Verify calculations around month/year boundaries
6. Use named ranges: For frequently used date ranges (e.g., "ProjectStart")
7. Validate inputs: Use data validation to ensure proper date formats

Automating Date Calculations with VBA

For repetitive tasks, consider creating custom VBA functions:

Function DaysUntil(TargetDate As Date) As Long
    DaysUntil = TargetDate - Date
End Function

Then use in your worksheet as =DaysUntil(A1)

Alternative Tools for Date Calculations

While Excel is powerful, consider these alternatives for specific needs:

• Python: Using datetime module for complex calculations
• JavaScript: For web-based date applications
• SQL: For database date queries (DATEDIFF function)
• Specialized software: Like project management tools for Gantt charts

Government Standards for Date Calculations

The National Institute of Standards and Technology (NIST) provides guidelines on date and time representations: NIST Time and Frequency Division

Frequently Asked Questions

Why does Excel show ###### instead of my date?

This typically indicates either:

• The column isn't wide enough to display the date
• The result is negative (future date)
• The cell contains an invalid date

Solution: Widen the column or check your formula for errors.

How do I calculate someone's age in Excel?

Use this formula:

=DATEDIF(BirthDate,TODAY(),"y") & " years, " & DATEDIF(BirthDate,TODAY(),"ym") & " months, " & DATEDIF(BirthDate,TODAY(),"md") & " days"

Can Excel handle dates before 1900?

No, Excel's date system starts at:

• January 1, 1900 (Windows versions)
• January 1, 1904 (Mac versions)

For earlier dates, you'll need to store them as text or use specialized add-ins.

How do I calculate the number of weeks between two dates?

Use this formula:

=ROUNDDOWN(DAYS(EndDate,StartDate)/7,0) & " weeks and " & MOD(DAYS(EndDate,StartDate),7) & " days"

Why is my DATEDIF function not working?

Common issues:

• Misspelled unit argument (must be in quotes)
• Start date is after end date
• Using in Excel versions before 2000
• Cell contains text that looks like a date but isn't recognized as one

Solution: Verify all arguments and ensure dates are properly formatted.

Conclusion

Mastering date calculations in Excel opens up powerful possibilities for data analysis, project management, and financial modeling. The key functions to remember are:

• DATEDIF for comprehensive date differences
• DAYS for simple day counts
• NETWORKDAYS for business day calculations
• TODAY() for dynamic current date references

By combining these functions with proper error handling and formatting, you can create robust date calculation systems that handle virtually any time-based scenario your work requires.

For the most accurate results, always test your formulas with known date ranges and consider edge cases like leap years and month-end dates. The interactive calculator at the top of this page demonstrates these principles in action - feel free to experiment with different dates and formats to see how Excel handles various scenarios.