One date in, every face of age
on a single screen.

What can one birth date tell you?

Enter a date to see your birthday-based age, days alive, generation label, birthstone, Western star sign, a birth-year animal, and the next age milestone. These are different ways to tell a story about the same date—not a single official record. The English results show international age; they do not display Korean or Japanese age cards.

Start with the birthday rule

International age is the current year minus the birth year, subtracting one if this year’s birthday has not arrived. For example, someone born on October 10, 2000 is 25 on September 27, 2026 and 26 on October 10. The number of days alive counts elapsed calendar days, so it answers a different question from age in years.

What the other cards mean

The generation card uses broad birth-year ranges, which differ between publishers and are not a scientific diagnosis of personality. Birthstones, Western star signs, and animal signs are cultural labels, not facts about a person’s abilities or future. This animal card uses the Gregorian birth year beginning January 1, not the lunar-new-year boundary sometimes used for Chinese zodiac signs. The milestone card highlights familiar birthdays; it is not a legal eligibility checker. Driving, voting, drinking, insurance, and retirement rules depend on location and circumstances. Confirm those with the relevant authority instead of relying on a birthday card.

How Korean age differs

In traditional Korean counting, a baby begins at one and gains a year on January 1. A person born on December 31 can therefore be two by that count the next day, while still zero by birthday-based age. Korea adopted international age as the general administrative rule in June 2023, but its official guidanceexplains that some laws retain different age thresholds. To compare all three Korean numbers on this site, use the Korean age tool.

When a family record uses a lunar date

The Lunar input converts a birth date once using a Chinese lunar-date table, then calculates age from that Gregorian date. It does not find the date of a recurring lunar birthday each year, and this age input has no leap-month selector. Korean lunar dates may differ from the Chinese table. If your record is Korean, verify the birth year and leap month with anauthoritative Korean calendar source, then enter the confirmed Gregorian birth date under Solar. This matters especially for dates near a lunar month boundary.

Share with the privacy trade-off in mind

Typing does not add the birth date to the address bar. Below the result, choose Preview result link, inspect the date-bearing address, then choose Copy reviewed link if the person concerned agrees. Opening it recalculates age on that day; it is not a frozen result image. Existing result links still work. We clear their date parameters from the current address after loading, but cannot erase the initial server request, logs or earlier history. Avoid public sharing of someone else’s birth date.

Questions people ask after seeing the result

This is an informational calculator, not a legal or identity-verification service. Use official records and local authorities for eligibility or document decisions.