PALLAS / CALCULATOR
Age Calculator
Calculate chronological age between two Gregorian calendar dates, total elapsed days and the next birthday. Date arithmetic stays local and does not depend on timezone-sensitive date parsing.
INPUT
Enter values
Method & formula
The calculator validates the dates as Gregorian calendar values, calculates completed years and months with month-end clamping, then counts the remaining days. A 29 February anniversary is treated as 28 February in non-leap years for this product calculation; that convention is not a legal-age rule.
- Chronological age = completed years + completed calendar months + remaining calendar days
- Total days = Gregorian ordinal(reference date) − Gregorian ordinal(birth date)
Example
From 29 February 2000 to 28 February 2025, this calculator reports 25 years, 0 months and 0 days under its explicit non-leap-year anniversary convention.
FAQ
How does the calculator handle 29 February birthdays?
For product calculations, the anniversary is 28 February in non-leap years. Legal rules can differ by jurisdiction, so this convention should not be used as legal advice.
Does daylight-saving time change the date-only result?
No. Date-only arithmetic does not parse the inputs as local-midnight timestamps. Optional times are reported as civil elapsed time and are not a zoned-time DST calculation.