How to Calculate Age in Excel: From Birthdate to Exact Years, Months, Days
Multiple methods for calculating age from birthdate, from simple DATEDIF to precise year/month/day breakdowns.
Calculating age sounds simple — but do you want years only? Years and months? The exact age in years, months, and days? Each requires a different approach. HR professionals often need this for employee tenure calculations.
Age in Complete Years
Using DATEDIF (the “undocumented” function that works perfectly):
=DATEDIF(birthdate, TODAY(), "Y")
This returns complete years of age. Someone born June 15, 2000 would show 24 years old in January 2025.
Age in Years and Months
Combine two DATEDIF calls:
=DATEDIF(A1,TODAY(),"Y")&" years, "&DATEDIF(A1,TODAY(),"YM")&" months"
The “YM” unit returns months remaining after full years.
Exact Age: Years, Months, Days
The complete breakdown:
=DATEDIF(A1,TODAY(),"Y")&" years, "&DATEDIF(A1,TODAY(),"YM")&" months, "&DATEDIF(A1,TODAY(),"MD")&" days"
“MD” returns days remaining after full months.
Alternative: YEARFRAC
For a decimal age:
=YEARFRAC(birthdate, TODAY())
Returns something like 24.58 years. Use INT() to get just the whole years.
Age as of a Specific Date
Replace TODAY() with any date to calculate age as of that date:
=DATEDIF(birthdate, specific_date, "Y")
Useful for determining eligibility on a past or future date.
Enter Dates Faster with a Real Date Picker
Excel doesn't have a built-in date picker. XLNavigator adds a calendar popup that makes date entry fast and error-free.
Related Reading
- Date Calculations — DATEDIF and more
- Date Entry Errors — prevent common mistakes
- Date Validation — restrict to valid dates
Official Resources
- DATEDIF function — calculate age and differences
- YEARFRAC function — fractional year calculation
Want more Excel tips like this?
Get our free guide: 10 Excel Shortcuts Microsoft Doesn't Tell You About
Join 3,000+ Excel users boosting their productivity.