Time & Date
Age Calculator
Calculate your exact age in years, months, days, and total days lived.
Calculate your exact age down to the day from your birth year, or find the age difference between two dates. Useful for forms requiring exact age, pension eligibility, legal age verification, and more.
Current Age
36 years old
- breakdown
- 36y 3m 27d
- total Days
- 13,268 days lived
- next Birthday
- 245 days until birthday
Formula and method
Age = Current Date - Birth Date
Subtracts birth date from current date, adjusting for month and day boundaries. Total days uses Unix timestamp difference divided by milliseconds per day.
Worked examples
Retirement eligibility check
- Birth Year:
- 1960
- Birth Month (1-12):
- 3
- Birth Day:
- 15
Current Age: 66 years old
Child age for school enrollment
- Birth Year:
- 2019
- Birth Month (1-12):
- 9
- Birth Day:
- 1
Current Age: 7 years old
Assumptions and limits
- Gregorian calendar
- Uses current system date
This tool provides an educational estimate. Rules, rates and personal circumstances can change the answer. Review the assumptions before relying on a result. Report a correction.
Common mistakes to avoid
- Using only birth year ignores the exact birthday — if your birthday is later in the year you may not have turned that age yet.
- Forgetting leap years when counting total days — every 4 years adds an extra day.
- Off-by-one errors at midnight on the birthday itself.
Frequently asked questions
What does "age in completed years" mean?
Most age calculations use completed years — you are 29 until the day you turn 30. Some Asian cultures use different systems (like the Korean age system where you are 1 at birth and gain a year every January 1).
How do I calculate someone's age for a legal form?
For legal purposes, age is the number of complete years from the date of birth to the current date. This calculator gives exact completed years, months, and days.