Age Calculator
Calculate your exact age in years, months, and days from your date of birth. See your age in total weeks, days, hours, and minutes, the weekday you were born, and a countdown to your next birthday.
How age is calculated
Age is measured in calendar years, months, and days rather than a simple division of total days. The calculator subtracts your birth date from the target date one unit at a time: it first finds the difference in days, borrowing from the previous month when the day-of-month is smaller, then the months, borrowing 12 from the years when needed.
This is why two people born the same number of days apart can show a slightly different number of months — month lengths vary from 28 to 31 days, and leap years add a 29th of February. Counting by calendar units keeps the result aligned with how birthdays actually fall.
Years vs. total days
- Calendar age: the headline figure — e.g. “34 years, 2 months, 11 days”. This is the legal and everyday meaning of age.
- Total months / weeks / days: the entire span expressed in one unit. Useful for infants (often described in weeks or months) and for precise record-keeping.
- Hours and minutes: a rough conversion (days × 24, × 60). It ignores the exact time of birth, so treat it as an approximation, not a stopwatch reading.
Common uses
Set the “age at date” field to a future or past date to answer questions like “how old will I be at graduation?” or “what was my age on a specific event date?”. Leaving it on today gives your current age.
The tool also reports the weekday you were born and a countdown to your next birthday, including the year you will be turning — handy for planning celebrations or eligibility dates (retirement, pension, age-restricted milestones).
Note: results use calendar dates only and do not account for time of day or time zones. For legal age determinations, always confirm with the rules of the relevant jurisdiction.