Exact age for forms and eligibility β how age is counted in the US, EU, Korea and Japan
2026-09-22
Most forms want your age on a specific date, and most countries count it the same way: you become a year older on your birthday. Korea officially adopted this international standard in June 2023, retiring the traditional system where a newborn was one and everyone aged on New Year's Day.
Open the calculator
International standard
Age = current year β birth year, minus one if your birthday has not yet passed this year. Born 15 March 1990, on 1 March 2026 you are 35; on 15 March you turn 36. Leap-day babies (29 Feb) legally age on 28 Feb or 1 Mar depending on jurisdiction.
Calendar-year age
Some rules use 'the year you turn X': Korean conscription and youth-protection law, Japanese school entry cohorts, and many sports age groups. There, everyone born in 1990 is treated as 36 throughout 2026 regardless of birthday. The calculator shows both.
Where exactness matters
- Insurance and pension eligibility dates
- Visa and immigration age limits (often 'under 30 on the date of application')
- Retirement age and Social Security full-benefit age
- Medical dosing for children, in months