Calculate exact age in years, months and days — plus how many days you have lived and when your next birthday is.
iHow it is calculated
Exact age is found by subtracting the birth date from today, expressed in years, months and days. The calculator also shows the total days, months and weeks lived:
age = today − birth date
For someone born on 15 June 1990, on 9 July 2026 the age is 36 years, 0 months and 24 days — about 13,174 days lived.
?Frequently asked questions
How is exact age calculated?
The birth date is subtracted from today and expressed in years, months and days. For example, someone born on 15 June 1990 was, on 9 July 2026, 36 years, 0 months and 24 days old.
Why does my age differ from “whole years”?
The usual age shows only completed years, but the exact calculation also adds the months and days since your last birthday, for a complete value.
How many days have I lived?
The calculator also shows the total days since birth. At about 36 years that is roughly 13,150 days, depending on the leap years passed.
How many months and weeks am I?
Besides years/months/days, you see the total months and weeks lived. 36 years is 432 months and over 1,870 weeks.
When is my next birthday?
The calculator shows the date of your next birthday and how many days remain, taking into account whether it has already passed this year.
What day of the week was I born?
The result includes the weekday of birth (Monday, Tuesday, etc.), computed exactly from the Gregorian calendar.
Does age account for a 29 February birthday?
Yes. For those born on 29 February, the birthday “falls” on 28 February or 1 March in non-leap years, and the calculation stays correct.
What is exact age used for?
Official forms, eligibility (retirement, voting, licences), medical calculations, and also finding a child’s age in months or days.
Can I find my age at a past date?
Yes, using the date-difference calculator: set the birth date as start and the desired date as end.