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Age Calculator

Exact age — down to the day — plus your birthday countdown.

"How old are you exactly?" turns out to be a fiddly calendar question — months have different lengths and leap years intrude. This calculator computes your precise age in years, months, and days as of today, plus fun totals: days and weeks alive, and the countdown to your next birthday.

Why people use this

Official forms, school enrollments, visa applications, "how old will I be when the mortgage ends," and birthday countdowns. People use this because exact age in years-months-days is surprisingly fiddly — months have different lengths and leap years exist.

How it works

1. Pick your date of birth in the date field.
2. The calculator compares it against today, borrowing days from the previous month when needed — the same method used for legal age calculations.
3. Read exact age, total days, total weeks, and days until your next birthday.

Common questions

How is exact age calculated?

Subtract birth year from current year, then adjust: if your birthday has not happened yet this year, subtract one. Months and days borrow from the previous month when the current day-of-month is smaller than the birth day.

How many days old am I?

The calculator shows this directly — expect roughly 365.25 times your age in years, since leap days add about one extra day every four years.

Can I calculate age at a past or future date?

This tool computes age as of today. For the gap between any two arbitrary dates, use the date difference calculator — it handles any pair of dates.

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