Age Calculator
Use this age calculator to find your exact age in years, months, and days from your birth date. This tool is helpful for forms, milestones, planning, and personal records.
Birth Date
Your Age
Enter your birth date to calculate your exact age.
How Age Is Calculated
Calculating your exact age sounds simple, but calendar quirks make it surprisingly interesting. Age is counted in complete years elapsed since your date of birth. Leap years (which add a February 29th every four years) mean that someone born on February 29th only has a "true" birthday every four years — they conventionally celebrate on February 28th or March 1st in non-leap years.
Beyond years, this calculator breaks your age down into years, months, and days, giving you a precise measure of how long you've been alive. This is useful for legal and official purposes — insurance policies, retirement eligibility, and certain government programs define age boundaries to the day.
How to Use This Calculator
- Enter your date of birth using the date picker or type it in.
- The calculator uses today's date automatically as the reference point.
- Click Calculate to see your exact age in years, months, and days.
Frequently Asked Questions
How is age calculated differently around the world?
Most Western countries count age from the last birthday (so you're 30 until the day you turn 31). In traditional Korean culture, everyone is considered 1 year old at birth and gains a year each January 1st regardless of actual birth month — a system called "Korean age." South Korea officially moved to the Western system in 2023.
What is the difference between chronological age and biological age?
Chronological age is simply the time elapsed since birth — what this calculator measures. Biological age reflects how old your body actually is based on health markers like cellular damage, cardiovascular fitness, and metabolic health. Two people of the same chronological age can have very different biological ages depending on genetics, lifestyle, and environment.
Can I use this to calculate someone else's age?
Yes — simply enter the other person's date of birth. This is handy for verifying ages for legal agreements, checking whether a child meets age requirements for a sports league or program, or satisfying everyday curiosity.