Time & Date · Age
Age Calculator
Calculate exact age in years, months, and days between a birth date and any other date — free, with no sign-in.
Age Calculator
Enter a date of birth, confirm the date to calculate age as of (defaults to today), then select Calculate.
How this calculation works
Age is counted in whole calendar years, then whole calendar months within the current year, then the remaining days — the same way a birthday is conventionally counted. When a birth date falls on the 29th, 30th, or 31st of a month, a calendar month that has no such day (for example, February in a non-leap year) uses that month's last day instead.
Examples
Someone born on 1 January 2000 turns exactly 24 years old on 1 January 2024 — 24 years, 0 months, 0 days. Someone born on 29 February 2000 turns 23 on 28 February 2023, since 2023 has no 29 February.
About this calculation
This uses the standard calendar-based definition of age — no external source citation is needed for it.
Related tools
More calculators are on the way — browse everything planned on the Home page.
Frequently asked questions
Why does the calculator ask for an "as of" date?
So you can calculate age as of any date — not only today. It defaults to today's date, but you can change it to see age at a past or future date.
Why does the calculator say my input is invalid?
Either the date of birth or the "as of" date is missing or not a real calendar date, or the date of birth is after the "as of" date.
Age Solution
Age
Result will appear here.
Calculation steps