Age Calculator
Find out exactly how old you are — or how old something is — in years, months and days. Enter a date of birth and an 'as of' date, and get the exact age plus totals in days, weeks and months.
How it works
The calculator subtracts the date of birth from the reference date, breaking the result into calendar years, months and remaining days, and also expresses the total elapsed time in days, weeks and months.
Age = (As-of date) − (Date of birth)Worked examples
Simple example
Born 1 January 1990 and measured on 1 January 2024 gives an exact age of 34 years, 0 months and 0 days.
Partial year
Born 15 June 1995 and measured on 10 March 2024 gives 28 years, 8 months and 24 days.
Frequently asked questions
How is age calculated?
Age is the elapsed time between a date of birth and a reference date, broken down into years, months and days.
How many days old am I?
Enter your date of birth and today's date; the 'Total days' result tells you exactly how many days old you are.
Does this account for leap years?
Yes. The calculator uses calendar dates, so leap years are included automatically.
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