Date & Time calculator
Age Calculator
Calculate calendar age in years, months, and days.
About the age calculator
The age calculator computes your exact age in years, months, and days from your birth date to any target date. It accounts for varying month lengths and leap years for precise results.
How to use this calculator
- 1
Enter birth date
Select your date of birth.
- 2
Enter target date
Select the date you want to calculate age for (defaults to today).
- 3
View results
See your age broken down into years, months, days, plus total weeks, hours, and minutes.
How the calculation works
Calendar components are subtracted with borrowing for incomplete months and years.
Example: Choose a birth date and a later target date to calculate completed calendar age.
How date calculations work
Calendar math is trickier than it seems. Months have 28–31 days, leap years add an extra day every four years (except century years not divisible by 400), and time zones complicate exact hour counts. Our calculators use UTC-based date arithmetic to ensure consistent results regardless of your local time zone.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about age calculator
How accurate is the age calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.