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Age Calculator

Calculate exact age in years, months, and days from a birth date.

36 yrs 8 mo 13 days

Born on a Monday

13,405
Total days
1,915
Total weeks
in 109d
Turns 37
440
Total months

Results are provided "as is" and may contain errors or inaccuracies - please verify them before relying on them, and use this tool at your own risk.

How it works

This counts whole years first, then whole months within the current year, then whatever days are left over - the same way you'd naturally answer "how old are you" with more precision than just a year count. It correctly borrows from the previous month when the day-of-month hasn't been reached yet this month (so someone born on the 30th isn't shown a negative number of days in a 28-day February).

Read the full guide

How to use it

  1. Enter a birth date.
  2. Optionally set a different "as of" date - it defaults to today.
  3. The exact age in years, months, and days appears instantly.

Examples

Born Mar 15, 2000, as of todaye.g. 26 years, 4 months, 8 days

Frequently asked

Why would I set an "as of" date instead of using today?
Useful for calculating someone's age on a specific past or future date - like how old a document's subject was on the day it was issued, rather than how old they are right now.
How are months and days calculated so precisely?
The calculation accounts for different month lengths - if the birth day hasn't occurred yet in the current month, it borrows a full month's worth of days from the previous calendar month rather than guessing a fixed 30-day month.