Calculate your exact age from your birthdate in years, months, weeks, days, hours, and minutes. Find out how many days until your next birthday, and compare ages between two dates.
Your Exact Age
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Total Days Lived—
Days Until Birthday—
Next Birthday—
Age in Different Units
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Approximate Value
Fun Age Facts
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Your Date
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How Age Is Calculated
Age is calculated by counting complete years, months, and days from the birth date to the reference date. The calculation accounts for leap years and varying month lengths.
For example: Born March 15, 1990 — as of April 23, 2026 = 36 years, 1 month, 8 days.
Age in Different Cultures
In Western tradition, age increases on each anniversary of birth. In East Asian tradition (Korean/Chinese reckoning), babies are considered 1 year old at birth, and everyone ages by 1 on New Year's Day — meaning a baby born December 31 is 2 years old on January 1 by this system.
Frequently Asked Questions
Medical screenings, legal milestones, and benefit eligibility are all tied to specific ages. Social Security eligibility starts at 62, Medicare at 65, and penalty-free 401(k) withdrawals at 59½. Some medication dosing and clinical protocols use exact age in months or weeks, particularly for children.
Age calculation counts actual calendar days and accounts for leap years. A person born January 31 aging to February 28 has completed 28 days of the next month — the calculator never rounds months to a flat 30 days. This is why results show exact years, months, and days.
In the traditional Korean system, babies are 1 year old at birth and everyone gains a year on January 1 regardless of birthday. South Korea officially adopted the international age system in 2023, but the traditional system is still culturally understood.
In the US, the legal age of adulthood is 18 — the age for voting, signing contracts, and military service. Some rights activate later: alcohol purchase at 21, car rental without a surcharge typically at 25. Retirement-related ages include 59½ (penalty-free retirement withdrawals), 62 (early Social Security), and 65 (Medicare).
Count the number of complete months from the birth date to today. A baby born May 15 is exactly 3 months old on August 15. Pediatricians track developmental milestones in months: sitting unsupported typically by 6–8 months, first words by 12 months, walking by 12–15 months. Knowing your baby's exact age in months helps interpret these guidelines correctly.
Chronological age is counted from birth. Gestational age (or corrected age) for premature babies is counted from the original due date, not the actual birth date. A baby born 8 weeks early who is 6 months old chronologically has a corrected age of only about 4 months. Healthcare providers use corrected age when assessing developmental milestones in preemies, typically until age 2.
Multiply your age in years by 365.25 (accounting for leap years) and add the days from your last birthday to today. A 30-year-old is approximately 10,957 days old. The calculator gives the exact count by working from your actual birth date, including all leap days along the way.