Age Calculator

To calculate your exact age, start with your date of birth and today's date. Subtract the birth year from the current year for a base age in years. If your birthday this year has not yet occurred, subtract one from that number. Then calculate the remaining months by counting from your last birthday to today's month. Finally, calculate the remaining days from the last complete month to today's date, accounting for the different number of days in each month. Leap years add complexity. February has 29 days in a leap year and 28 in all others. The calculator handles all of this automatically using calendar-aware date logic, giving you exact years, months, and days without any manual calculation.

The number of days you have lived equals your age in complete years multiplied by 365, plus the number of leap year days within your lifetime (one additional day for each February 29 that has passed since your birth), plus the remaining days since your last birthday. For reference: a 25-year-old has lived approximately 9,131 days, a 30-year-old approximately 10,957 days, a 40-year-old approximately 14,610 days, and a 50-year-old approximately 18,263 days. Enter your date of birth in the calculator to get your exact day count, including how far you are from your next milestone day (10,000, 15,000, 20,000, etc.).

For a person born on February 29, the legal birthday in a non-leap year varies by jurisdiction and purpose. Most US states use February 28 as the effective birthday for legal age-of-majority purposes meaning a February 29 birth person turns 21 on February 28 in a non-leap year for purposes of alcohol purchase and other age-restricted activities. The Social Security Administration and several federal agencies default to March 1 as the non-leap-year birthday. For driving privileges, most state DMVs use February 28. For practical purposes in non-leap years, most leaplings celebrate and handle legal matters on February 28. The calculator provides both options February 28 and March 1 for February 29 birthdays in non-leap years.

In the United States, 18 is the age of majority in all 50 states the age at which a person gains full legal adult status, including the right to vote, sign legally binding contracts, join the military without parental consent, and be tried as an adult in criminal court. Some specific legal rights require higher minimum ages: purchasing alcohol requires age 21 in all 50 states under the National Minimum Drinking Age Act; purchasing a handgun from a federally licensed dealer requires age 21; and car rental companies typically charge additional fees for drivers under 25. The age of majority for emancipation proceedings, marriage with parental consent, and other legal purposes varies by state.

Chronological age is the time elapsed from a person's date of birth to what is typically meant when someone states their age. Adjusted age (also called corrected age) applies to premature infants and is calculated by subtracting the number of weeks premature from the chronological age. The American Academy of Pediatrics recommends using corrected age for developmental assessments evaluating motor milestones, language, and growth until approximately 24 to 36 months of chronological age. A baby born 8 weeks premature who is 6 months old chronologically has a corrected age of approximately 4 months and should be compared to 4-month developmental milestones, not 6-month milestones. Using chronological age for premature infants causes them to appear developmentally delayed when they may be developing entirely normally for their gestational experience.

You can begin claiming Social Security retirement benefits as early as age 62, but doing so results in a permanent reduction of approximately 30% compared to your Full Retirement Age (FRA) benefit. The Full Retirement Age for anyone born in 1960 or later is 67, the age at which you receive your full calculated benefit with no reduction. For every year you delay claiming past your FRA up to age 70, your monthly benefit permanently increases by approximately 8%. Claiming at 70 instead of 62 can result in a monthly benefit that is approximately 77% higher. The break-even age where the cumulative higher benefit surpasses the total received by claiming earlier is typically around age 80 to 82. Medicare eligibility begins separately at age 65, regardless of when you claim Social Security.