Age Calculator
Find your exact age, zodiac sign, next birthday countdown, and much more.
How to Use the Age Calculator
- 1Choose your preferred date format — UK (DD/MM/YYYY) or US (MM/DD/YYYY) — using the toggle at the top.
- 2Click the date field and select your date of birth using the browser's date picker.
- 3Press Calculate Age to instantly see your exact age, total days lived, and more.
- 4Review your results: exact age in years/months/days, next birthday countdown, zodiac sign, and Chinese zodiac.
- 5Born on 29 February? The calculator correctly uses 28 February in non-leap years for your next birthday.
Frequently Asked Questions
How is exact age calculated?
The calculator subtracts your date of birth from today's date using calendar-accurate arithmetic, accounting for varying month lengths and leap years. It returns the full number of completed years, months, and remaining days separately.
How are leap years counted?
A year is a leap year if it is divisible by 4, except century years (divisible by 100) which must also be divisible by 400. The calculator counts every leap year from your birth year up to and including the current year.
How is the zodiac sign determined?
The Western zodiac sign is based solely on your birth month and day, not the year. The calculator uses the standard date boundaries for all 12 signs (e.g. Aries runs 21 March – 19 April).
How is the Chinese zodiac year calculated?
The Chinese zodiac operates on a 12-year cycle: Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Goat, Monkey, Rooster, Dog, Pig. The cycle anchors to 1900 as a Rat year, so your sign is (birth year − 1900) mod 12.
What happens if I was born on 29 February?
In non-leap years your birthday is treated as 28 February for the purpose of calculating days until your next birthday. Your exact age in years is still computed correctly since a full year has elapsed by 28 February in those years.
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