Age Calculator: Calculate Your Exact Age in Years, Months, and Days

Calculate your exact age or anyone's age in years, months, weeks, and days. Find out the next birthday countdown and how many days you've been alive.

Mathematical Audit

How Age Is Calculated

Age is calculated by subtracting the birth date from the current date, accounting for whether the birthday has occurred yet in the current year.

Years = Current Year − Birth Year (adjust if birthday hasn't occurred this year)
Months = (Current Month − Birth Month + 12) % 12 (adjust for partial years)
Days = Current Day − Birth Day (adjusted per month)
Total Days Alive = (Current Date − Birth Date) in milliseconds ÷ 86,400,000

For people born on February 29 (leap day), their birthday is typically celebrated on February 28 or March 1 in non-leap years. This calculator uses February 28 by default.

Operational Guide

How to Use the Age Calculator

1

Enter your birth date

Select or type your date of birth.

2

Set the target date

Default is today's date for current age. Change to any date for age-at-a-date calculations.

3

Click Calculate

See exact age in years, months, days, total days, weeks, hours, and minutes.

Real-World Scenario Example

"Born on March 15, 1990. As of May 31, 2026, age = 36 years, 2 months, 16 days = 13,226 days alive."

Inputs

birthDate:1990-03-15
targetDate:2026-05-31

Result

36 years, 2 months, 16 days | 13,226 days alive

Important Disclaimer

Age calculations are based on the Gregorian calendar and the current UTC date. Results may differ slightly by timezone. For legal age verification purposes, consult official documentation.