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Age Calculator

Find out exactly how old you are and when your next birthday lands.

Processed locally — nothing is uploaded

About Age Calculator

Gives the breakdown as well as the headline number: total days lived, and how long remains until the next birthday. Useful for forms that want an exact age on a particular date rather than on today's.

Find your exact age in years, months and days from your date of birth, plus totals in weeks and days and a countdown to your next birthday. The dates you enter never leave your browser.

Calculate an exact age in years, months and days from a date of birth, plus the totals in weeks, days, hours, minutes and seconds, and a countdown to the next birthday. It is the quick way to answer 'how old am I?' or to work out anyone's precise age on a given date.

Set the 'as of' date to any day to find an age in the past or the future, not only today. That is the part most age calculators leave out, and it is exactly what forms and eligibility rules tend to ask for.

Learn how this works

Everyday Calculations & Conversions Made SimpleConvert units and time zones, and calculate age, BMI, discounts and loan EMIs — a plain-English guide with free in-browser tools.7 min read

Frequently asked questions

How is age calculated exactly?

By calendar difference rather than dividing days by 365.25 — years first, then months, then remaining days. That is why the result matches how people actually count age, including through leap years.

How are birthdays on 29 February handled?

In non-leap years the birthday is treated as falling on 1 March for counting purposes, which is the common legal convention in most jurisdictions. Some treat it as 28 February, so check if it matters formally.

Can I calculate age at a specific past or future date?

Yes — set the target date rather than using today. That is what you need for eligibility cut-offs, school year placement, or working out someone's age at a historical event.

Common Use Cases

  • •Working out an exact age in years, months and days
  • •Checking age eligibility against a specific cut-off date
  • •Finding how many days remain until a birthday or milestone

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Age Calculator

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