birthday_cake Age Calculator
Calculate your exact age in years, months, and days. Find out how many days you have been alive and count down to your next birthday.
Enter values and click Calculate.
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Frequently Asked Questions - Age Calculator
How is age calculated exactly?
Age is typically calculated as the difference between your birth date and the current date. The years, months, and days are computed by comparing the year, month, and day components separately, accounting for month boundaries and leap years.
How do leap years affect age calculations?
Leap years add an extra day (February 29) every four years, with some exceptions for century years not divisible by 400. Age calculations account for this by using actual calendar dates rather than assuming 365 days per year.
At what age am I considered an adult in different countries?
The age of majority is 18 in most countries including the US, UK, Canada, and Australia. It is 19 in South Korea and Algeria, 20 in Japan and Thailand, and 21 in Singapore and Mississippi (US). Some rights like drinking alcohol have different age thresholds.
How do different cultures calculate age?
In Korea, you are considered age 1 at birth and everyone gains a year on New Year's Day. In China, traditional age counting adds a year at each Lunar New Year. Some cultures count the time in the womb as the first year of life.
What is a half-birthday and why do people celebrate it?
A half-birthday is the date exactly six months from your actual birthday. People with birthdays near major holidays, summer vacations, or February 29 (leap year) often celebrate half-birthdays to ensure they can enjoy a proper celebration with friends.
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