Age Calculator

Enter a date of birth to get your exact age in years, months and days, plus the total in days, weeks and months — and a countdown to the next birthday. Nothing is uploaded — the dates stay in your browser.

Date of birth As of

Enter your date of birth to see your age.

The countdown appears once a birth date is entered.

How the age is worked out

Counting from the calendar, not by dividing days. Age is the whole years, then months, then days between the date of birth and the reference date.
Borrowing across months. When the day-of-month has not yet been reached, the calculation borrows the length of the previous month — which is why February ages shift by a day or two versus a naive division.
Today by default. Leave “as of” blank to use today’s date; set it to a past or future date to see the age on that day.
Leap-day birthdays. If you were born on 29 February, the next birthday in a non-leap year is treated as 1 March.

Where an exact age is asked for

Forms that ask for an age usually want the one you get by counting from the date of birth, which is what this calculator returns. Age also drives eligibility cut-offs — child fares and passports, school year groups, and the date a passport or visa application must show a certain age. If a rule is written as “under 16 on the date of travel”, set “as of” to the travel date rather than today. For date arithmetic on applications, the business days calculator counts working days and the passport validity calculator checks the six-month rule.

Related tools

Count working days with the business days calculator; check passport and photo dates with the passport validity calculator and the six-month rule calculator; plan a stay with the 90/180 day calculator; and convert timestamps with the epoch converter.

Frequently asked questions

How do I calculate my age in years, months and days?
Count whole years from your date of birth to the reference date, then the remaining whole months, then the leftover days. The calculator does this for you in the calendar.

Why is the number of days not a simple year × 365?
Because leap years add a day. Totalling days and dividing by 365 gives an average, not your exact age — counting from the calendar, as here, gives the figure forms expect.

What if I was born on 29 February?
In a non-leap year the calculator treats the next birthday as 1 March, since 29 February does not exist that year.

Can I find my age on a future date?
Yes. Set “as of” to that date and the age is shown for that day, which is useful for “under 16 on the date of travel” style rules.

How many days until my next birthday?
The countdown shows the next birthday strictly after the reference date, and how old you will turn.

Is my date of birth sent anywhere?
No. The calculation runs entirely in your browser; the dates are never uploaded or stored.

Honest limits: the result is calendar arithmetic on the dates you type, using the local date as “today” when you leave “as of” blank. It is a calculation, not an official record — where a form or a rule sets an age cut-off, confirm the exact date that applies to you.

All tools → Count business days →