Short answer
To find exact age, subtract the birth date from the target date in years, months and days, borrowing the previous month's days when the day count goes negative. From 14 May 1995 to 5 Feb 2025 that gives 29 years, 8 months and 22 days, or 10,860 days.
1. The method
- 1Subtract the birth year from the target year.
- 2Subtract the birth month from the target month. If negative, take one year off the years and add 12 months.
- 3Subtract the birth day from the target day. If negative, take one month off and add the number of days in the previous month.
2. Worked example
Born 14 May 1995, target date 5 February 2025.
- 2025 − 1995 = 30 years; month 2 − 5 = −3, so 29 years and 9 months.
- Day 5 − 14 = −9, so borrow January's 31 days: 22 days and 8 months.
- Result: 29 years, 8 months, 22 days.
- Total days between the dates: 10,860, which is 1,551 weeks and 3 days.
3. In a spreadsheet
=DATEDIF(A1, TODAY(), "Y") gives completed years; use "YM" for leftover months and "MD" for leftover days.
Skip the arithmetic with the Age Calculator. For leap-day births see how age works for 29 February.
4. Frequently asked questions
How do I calculate my exact age?expand_more
Subtract your birth date from the target date in years, months and days, borrowing the previous month's days if the day count is negative.
How many days old am I?expand_more
Count the whole days between your birth date and today. From 14 May 1995 to 5 Feb 2025 it is 10,860 days.
Why can two calculators show different days?expand_more
They may borrow from different months when the day count is negative. The calendar total of days is the same either way.
What is completed age?expand_more
The number of full years since birth. You turn a year older on your birthday, not before.