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Age Calculator

Our age calculator computes your exact age in years, months, days, hours, minutes, and seconds — accounting for leap years and time zones. It also tells you the day of the week you were born, the day of the week your next birthday falls on, and how many days until your next birthday.

Total Days

Total Weeks

Total Months

Total Hours

Born On

Days to Birthday

Your Age

years old

Years
Months
Days
Next Birthday

Enter your date of birth above

How Age Is Calculated

Age is measured by counting the number of complete years that have passed since your date of birth. A birthday marks the start of a new year — your age doesn't change until the exact calendar date of your birth arrives each year.

For example, if you were born on June 15, 1990 and today is May 14, 2026, you are 35 years old. You will turn 36 on June 15, 2026 — 32 days from now.

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About the Age Calculator

Our age calculator computes your exact age in years, months, days, hours, minutes, and seconds — accounting for leap years and time zones. It also tells you the day of the week you were born, the day of the week your next birthday falls on, and how many days until your next birthday.

How to use it

  1. Enter your date of birth (and optionally time of birth for hour-level precision).
  2. See your exact age in multiple units: years + months + days, or total days, hours, minutes.
  3. View your birth day of the week and next birthday countdown.
  4. Calculate the age difference between two people, or the age on a specific historical date.

Formula & methodology

Age in years = floor((reference date − birth date) / 365.25). Precise: count full calendar years, then remaining months, then remaining days. Total days = (reference date − birth date) in days. Hours = days × 24. Minutes = hours × 60. Next birthday: next occurrence of birth month/day after today. Leap year handling: Feb 29 birthdays celebrated on Feb 28 or Mar 1 in non-leap years.

Common use cases

  • Legal: verifying age for driving, voting, or drinking age milestones
  • Medical: precise age for pediatric dosing calculations
  • Insurance: age at nearest birthday for premium calculations
  • HR: calculating years of service for vesting, PTO accrual, retirement
  • Fun: finding out how many days, hours, or seconds old you are

Frequently asked questions

People born on Feb 29 (leap day) celebrate their "real" birthday every 4 years. In non-leap years, different countries have different legal conventions: in the US and UK, the birthday is typically observed on March 1 for legal purposes. In some countries, Feb 28. For legal age milestones (turning 18 for voting), check your jurisdiction — a Feb 29 birthday turning 18 in a non-leap year may legally occur on either Feb 28 or March 1 depending on local law.
The ambiguity lies in month lengths. A person born March 31 turns 1 month old on April 30 (not April 31, which doesn't exist). Different calculators handle this differently: some count the last day of April as the 1-month mark; others say 1 month on May 1. Similarly, "exactly 1 year" is 365 or 366 days depending on whether a Feb 29 falls in between. Our calculator follows the most common civil convention used in legal and medical contexts.

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How Old Am I If Born In…

Select your birth year for a dedicated page showing your current age, generation, milestone birthdays, and more.

1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025