Advanced options
What The Age Calculator Works Out
- Exact age: years, months and days between your date of birth and the chosen date (today by default). It counts complete years first, then complete calendar months, then the remaining days, borrowing from the previous month where needed, which is the convention used for official purposes.
- Next birthday: the days until your birthday next comes round and the weekday it falls on. In England and Wales you legally reach a new age at the start of your birthday; under the old common law rule you attained it the day before, until statute fixed the modern rule in 1969.
- Day you were born: the weekday of your birth. If you were born on 29 February you have a birthday only in leap years; the calculator treats 1 March as the anniversary in other years, matching how UK law treats leap-day birthdays for age thresholds.
- Totals table: your age in total months, weeks, days and approximate hours, useful for milestone spotting and for forms that ask for age in months for babies and toddlers.
- Date you turn a chosen age (advanced): the exact date you reach any age, such as 18, 21, 60 for an older person's bus pass in England, or 66 to 68 for State Pension age, and how far away or long ago that is.
- Next day milestone (advanced): the date of your next round-number day of life, every 1,000, 5,000 or 10,000 days. Your 10,000th day lands about seven and a half weeks after your 27th birthday and your 20,000th shortly after turning 54.
- Star sign (advanced): the Western zodiac sign for your birthday, using the usual boundary dates (for example Aries from 21 March to 19 April). Boundary days can differ by a day between sources.
- Chinese zodiac (advanced): the animal for your birth year in the twelve-year cycle. Because the Chinese year starts between 21 January and 20 February, January and early February birthdays may belong to the previous year's animal, and the result says so.
- Age gap (advanced): enter someone else's date of birth to see the difference in years, months and days, and in total days.