DailyNumeric
Age, Date & Calendar

Age Calculator

Enter your date of birth to find your exact age in years, months, and days — plus totals in days, weeks, months, and hours.

Your calculation is performed in your browser.
Defaults to today if left blank.

Enter your date of birth above to calculate your age.

How it works

The calculator compares the year, month, and day of your birth date with the selected calculation date (today, by default). It counts full years first, then full months left over, then full days left over, the same way you would count on a calendar.

Formula & methodology

The calculator uses calendar subtraction, the way you would count on a paper calendar. It counts full years first, then full months, then leftover days. When the day of the month is too small to subtract, it borrows the real length of the previous month rather than assuming 30 days.

Exact ageAge = Target date − Date of birth (as years, months, days)
Total daysTotal days = Target date − Date of birth
Total weeksTotal weeks = ⌊ Total days ÷ 7 ⌋
Total monthsTotal months = (Years × 12) + Months
Total hoursTotal hours = Total days × 24

What each term means

Target date
The date you are calculating your age on (today by default).
Round down (⌊ ⌋)
Round down to the nearest whole number.
Years, Months
Complete years and complete months from the calendar subtraction.

Worked example

If you were born on March 15, 2000 and calculate your age on September 13, 2026, you are 26 years, 5 months, and 29 days old — 9,678 total days.

Common uses

  • —Visa, passport, and legal forms that ask for age in exact years, months, and days rather than just a birth year.
  • —Insurance applications and eligibility checks, where premiums or coverage can depend on precise age.
  • —School, program, or competition enrollment cutoffs based on a child’s exact age on a specific date.
  • —Medical and pediatric records, where dosage or growth-chart placement depends on precise age rather than a rounded year.
  • —Milestone tracking, such as finding the exact date you’ll turn 10,000 days old or reach a round-number birthday.

Important notes

  • —If you were born on February 29, this calculator treats March 1 as the day your age in years increases during non-leap years — the same convention many age calculators use, since February 29 simply doesn’t exist in those years.
  • —You can calculate your age as of any past or future date, not just today.