Enter Date Details
Enter your date of birth and hit Calculate Age
How Age is Calculated
Age is worked out the way people actually count it, by calendar rather than by dividing days. The calculator subtracts the day, month and year separately and borrows where needed: if the day of the month has not yet been reached, it takes a month and adds that month's real number of days.
This matters because months are unequal. Counting from 31 January to 1 March is not the same number of days as counting from 31 March to 1 May, and a pure day-division approach reports a confusing result.
How to Use It
- Enter your date of birth.
- Leave the second date as today, or set it to any other date to find your age as on that day.
- Use the quick buttons to jump to today or the start of the next year.
- Click Calculate Age to see the breakdown.
What Each Figure Means
- Years, months and days is the calendar age, the figure forms usually ask for.
- Total months is the whole number of complete months elapsed.
- Total days is the exact day count between the two dates.
- Total hours is derived from total days, so it assumes whole days rather than a time of birth.
- Next birthday counts the days remaining from the chosen date.
Common Uses
- Filling in an exact age on a form, application or admission document.
- Checking eligibility where a cut-off date applies rather than today's date.
- Working out an age on a past or future date, such as a scheme deadline.
- Settling how many days there are between two dates.
Notes and Limitations
- Time of day is ignored. Both dates are treated as whole calendar days, so the hours figure is days multiplied by 24.
- Dates are read in your device's local time zone.
- The zodiac sign uses conventional western date ranges, and the season shown is the Northern Hemisphere one.
- Some official documents compute age by their own convention, such as age as on a fixed date each year. Check the rule that applies to your form.
Privacy and Processing
The dates you enter stay in your browser. Nothing is uploaded, stored or logged by this page.
Age Calculator FAQ
How is exact age calculated?
The day, month and year are subtracted separately, borrowing where needed. If the day of the month has not yet been reached, a month is borrowed and its real number of days added. This matches how people actually count age by calendar rather than by dividing total days.
Can I calculate my age on a date other than today?
Yes. Set the second date to any past or future date to find your age as on that day. This is useful when a form or scheme applies a fixed cut-off date rather than today.
Why does my age in months not match my age in years times twelve?
Total months counts every complete month elapsed, while years and months splits that same span into whole years plus a remainder. Both describe the same period in different units.
How is the total hours figure worked out?
It is the total number of days multiplied by 24. Time of birth is not used, so both dates are treated as whole calendar days.
Does the calculator handle leap years?
Yes. Actual month lengths are used when borrowing days, so February in a leap year is counted correctly.
Is my date of birth stored?
No. The calculation runs entirely in your browser and nothing you enter is uploaded, stored or logged.
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