How age is worked out, and when a 29 February baby has a birthday.
Age in years, months and days, counted from the last birthday, with the rule for a 29 February birthday in common years and a few fun facts.
By Suraj Kumar4 min read
Age is whole years to the last birthday, then the months and days since. One day of the year makes that harder.
Years, then months, then days.
The Age calculator counts the whole years to your last birthday, then the whole months since, then the days left over. It also gives the total in days, the next birthday and its weekday, and how many days until it.
Born on 29 February.
In a common year there is no 29 February, so the law has to choose. Hong Kong's Age of Majority ordinance and Taiwan's Civil Code count 1 March; others count 28 February, and many people celebrate then. The calculator uses 1 March unless you choose 28 February under More options, and says which it used.
The fun part, with its working.
Under the answer are facts with their rules: the day you turn 10,000 days old, when a billion seconds pass (11,574 days, 1 hour and 46 minutes, so the hour depends on when you were born), your half birthday, and your age in the years of other planets, from the times NASA gives for each to go round the Sun.
Further reading
Topics: age calculator · how old am i · calculate age · age in days · date of birth calculator · leap day birthday
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