- How do I calculate my exact age from my date of birth?
- CDC/NCHS describes age as age at last birthday, often calculated from a person's date of birth and a reference date. This calculator follows that same calendar-based model and then shows the remaining months and days.
- Can I check how old I was or will be on a different date?
- Yes. Change the second date field to any past or future day to see the age on that specific date.
- Why does February 29 affect age calculations?
- NIST explains that leap years have 366 days and that century years are leap years only when divisible by 400. Because February 29 does not appear every year, calendar-based age calculations need a consistent comparison point in non-leap years.
- Can I calculate a child's age in months?
- Yes. CDC child and teen BMI tools support age by years and months as well as date of birth and date of measurement. This calculator can help when you need a month-level age before entering it elsewhere.
- Why do some forms ask for date of birth instead of approximate age?
- Exact age can change depending on the reference date, while date of birth stays stable. The U.S. Census Bureau notes that age and date-of-birth data are used to plan and fund programs for different age groups, which is one reason official workflows often start with birth date.
- Does this tool show completed years or decimal age?
- It shows completed calendar years first, then the remaining months and days. That is closer to the official age-at-last-birthday model than a decimal-style age.
- Can I use this age calculator for a future date?
- Yes. Change the reference date to a future day to check how old someone will be on that date and how close the next birthday is. This is useful when age-based rules depend on a specific future date.
- Does this tool also show total days lived?
- Yes. The result includes total days, weeks, and months in addition to the standard years, months, and days breakdown.
- Is my birth date stored anywhere?
- The calculation runs in the browser. If you use the copy-link action, the selected dates are added to the URL so the result can be reopened or shared.