Age Calculator

When to use?

Use it to find your exact age, see whether this year's birthday has passed, and how many days remain until your next birthday.

How to use

• Enter your date of birth.
• Choose a reference date (default: today).
• Your age, and days until your next birthday, are shown.

Input Explanation

Choose your birth date and the reference date for the calculation.

Calculation Basis

Age = reference year − birth year, minus 1 if the birthday has not yet passed on the reference date.

Usage Examples

• Check your age - Enter your birth date to find your age as of today.
• Find your next birthday - See how many days remain until your next birthday.
• Verify age for documents - Confirm the exact age to enter on contracts or application forms.

Examples

• Born 1995-08-15, reference 2025-05-12 → 29 (birthday not yet reached)
• Born 2010-12-25, reference 2025-05-12 → 14, 227 days to next birthday

Cautions

• The basis for legal age, full age, and year-based age differs by country and system.
• The applicable age can differ based on when legal effect begins on the birthday and how specific laws interpret the reference date.

Guides

Calculating age

Age is the current year minus the birth year if the birthday has passed, or that value minus 1 if it has not. From 2023, Korean official documents standardized on full (international) age.

Difference from counted age

Korean counted age starts at 1 at birth and adds a year every January 1. Korea uses counted age casually but full age for medical and legal purposes.

FAQ

How is age calculated?

Subtract the birth year from the reference year, then subtract 1 if the birthday has not passed by the reference date.

What about a leap-day (Feb 29) birthday?

In common years the birthday is treated as Feb 28 or Mar 1; in leap years, Feb 29 applies as-is.

Can I use a date other than today?

Yes. Choose any reference date to calculate age as of that date.

Does it count days to the next birthday?

Yes, it shows the number of days remaining until your next birthday.

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