Age Calculator
Enter a date of birth to get an exact age, in years, months, and days.
Why the year/month/day breakdown can look unusual
Age here is calculated by counting full years, then full months in the remainder, then remaining days — the same way you'd count age by hand. Because months have different lengths, the "days" figure isn't a fixed number and can range from 0 to 30.
About the Age Calculator
The Age Calculator works out how old someone is from a date of birth, counting complete years, months and days up to a date you choose (today by default). It also shows the total number of days you have lived and how long remains until the next birthday, which is handy for forms, school admissions, insurance and eligibility checks that ask for age on a specific cut-off date.
Age is counted the way people normally say it: a birthday adds a year only when the calendar day arrives. Months have different lengths and leap years add a 29 February, so the tool borrows days from the previous month when needed instead of using a fixed 30-day month. Everything is calculated in your browser from the two dates you enter.
How to use it
- Pick your date of birth using the date field.
- Leave the second date as today, or change it to the date on which you need your age (for example an exam cut-off).
- Read the result in years, months and days, plus total days, weeks and hours lived.
- Change either date to compare ages on different dates.
Tips and good to know
- For an official form, use the cut-off date stated by the authority rather than today's date.
- A person born on 29 February is normally treated as turning a year older on 28 February or 1 March depending on local rules; check the rule that applies to you.
- The total-days figure is useful for milestones such as 10,000 days old.
Frequently asked questions
Does it count the day of birth itself?
The birth date is the starting point, so the day you were born is day zero. A person born yesterday is one day old today.
Why does my age in months look odd at month ends?
Months differ in length. If you were born on the 31st, the tool uses the last day of shorter months, so results can differ by a day from a manual count.
Is my date of birth stored anywhere?
No. The calculation happens in your browser and nothing is sent to a server.