Unit Converter
Age Calculator
Calculate exact age in years, months, and days from a birth date to any reference date.
Years
Months
Days
Total days
Formula and usage notes
Use the age calculator for forms, school records, eligibility checks, milestones, and date planning.
The calculator subtracts calendar years, months, and days, then adjusts when the day or month has not been reached yet.
Practical examples
Practical examples 1
Birth date to today gives current age
Practical examples 2
2000-01-01 to 2026-01-01 = 26 years
Practical examples 3
Use a future date to check age on an event day
Practical examples 4
Use a past date to verify age on a historical record
Frequently asked questions
Does the calculator include leap years?
Yes. It works with calendar dates, so leap years and month lengths are included in the day count.
Can I calculate age on a future date?
Yes. Set the reference date to the event date.
Why not just divide days by 365?
Calendar age depends on months and birthdays, so exact age is not the same as a simple day average.