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Everyday · Age

Age Calculator

Exact age in years, months and days — plus the countdown to your next birthday.

Leave blank to use today. Set a date to find the age at that point in time.

Reading your result

Fill in every field and the steps will be spelled out here.

How it is calculated

age = reference year - birth year (minus 1 if the birthday has not occurred yet) exact age = whole years, then remaining months, then remaining days

Age here is counted the way almost every country counts it: the day you are born you are zero, and you gain a year on each birthday. The calculator also breaks that down into whole years, then the leftover months and days.

The total days lived figure counts actual calendar days, leap days included. It is a different number from years multiplied by 365, and the gap grows by roughly one day every four years.

For anyone born on 29 February, there is no birthday in a common year. This calculator treats the birthday as having passed once 28 February is over, which matches how most legal systems handle a date that does not exist in a given month.

Setting the as of date lets you answer a different question: how old someone was, or will be, on a particular day. Useful for eligibility cut-offs, school year boundaries, and contracts that turn on an age at a fixed date.

Frequently asked questions

Why is total days not just age times 365?

Because of leap years. Roughly one year in four has 366 days, so the true count runs ahead of a simple multiplication by about a day every four years.

How is someone born on 29 February handled?

In a common year the birthday is treated as passing at the end of 28 February. That follows the usual legal rule that when a month lacks the relevant day, the last day of that month applies.

Can I find an age on a past or future date?

Yes. Set the "as of" field to any date and the calculation runs against that day instead of today. Leave it blank to use today.

Does this handle time zones?

It works on calendar dates only, using your device’s local date. If a cut-off is being applied in a different time zone, check which zone governs it.

Related calculators

This calculator works on calendar dates. Where a specific law, contract or institution defines age differently, that definition takes precedence. For eligibility that turns on an exact cut-off, confirm with the body concerned.