Age Calculator Online Free

How to calculate an age

Enter a date of birth. You get the age in years, months and days, along with the total in days and the time remaining until the next birthday.

Why the day count is not obvious

Age arithmetic looks trivial and is not, because months have different lengths and leap years interrupt the pattern. "Three months old" means something different depending on whether those months were January to March or June to August. The calculation here works down from years to months to days, borrowing correctly from the previous month, which is the convention used for official purposes.

Leap days are handled properly. Someone born on 29 February has a birthday that exists roughly once every four years, and most legal systems treat 1 March as the anniversary in ordinary years.

Where exact ages matter

• Government forms and competitive exams with an age cut-off measured to the day on a specified date.
• School admissions, which usually set a minimum age as of a fixed month.
• Visa and pension eligibility rules stated in completed years.
• Medical dosing for infants, which is often calculated in weeks rather than months.

Where a form specifies "age as on" a particular date, calculate against that date rather than today. The gap between the two is exactly the kind of detail that gets applications rejected.

Frequently asked questions

Which date system does it use?

The Gregorian calendar, the civil standard almost everywhere.

Can I use it for future dates?

It is designed for dates in the past. For a date ahead of today, the result is a countdown rather than an age.

Is my date of birth sent anywhere?

No. The calculation happens entirely in your browser, and nothing is stored.

Why does my age differ by a day from another calculator?

Tools disagree on whether to count the birth day itself and on time zones. A one-day difference is usually one of those two.