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Age Calculator

Enter a date of birth to get the exact age in years, months and days. You also get the total months, weeks, days and hours lived, the weekday of birth, and a countdown to the next birthday. Change the second date to find an age on any past or future day.

Quick examples
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Age36 years, 4 months, 26 days
Completed years
36
Total months
436
Total weeks
1,899
Total days
13,298
Total hours
319,152
Born on a
Tuesday
Next birthday
Sat, May 15, 2027
Days until next birthday
216

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    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Age = date − date of birth, counted in whole years, then whole months, then days
      Total days = number of calendar days between the two dates

      How to use it

      1. Enter the date of birth.
      2. Leave the second date as today, or change it to find the age on another date.
      3. Read the age; the rows below give the same span in other units.

      Worked examples

      Born May 15, 1990 — age on October 11, 2026

      Age
      36 years, 4 months, 26 days
      Total days
      13,298
      Total weeks
      1,899
      Days until next birthday
      216

      Born January 1, 2000 — age on January 1, 2026

      Age
      26 years, 0 months, 0 days
      Total months
      312
      Born on a
      Saturday

      How the months and days are counted

      Years are counted first, then full months, then leftover days. Because months differ in length, the “days” part depends on which month the count ends in: someone born on the 31st has a birthday month-anniversary on the last day of shorter months.

      People born on February 29 are treated as having their birthday on February 28 in years that are not leap years, which is the convention most legal systems use.

      Different age systems

      This calculator uses the international system: you are 0 at birth and gain a year on each birthday. Traditional East Asian age reckoning counts a newborn as 1 and adds a year at New Year, so it can be one or two years higher. South Korea switched to the international system for official use in 2023.

      Questions people ask

      How old am I if I was born in 2000?

      You turn 26 during 2026. Before your birthday that year you are 25; on and after it you are 26.

      How many days old am I?

      Enter your date of birth and read “Total days”. Someone born on May 15, 1990 was 13,298 days old on October 11, 2026.

      Does it count leap years?

      Yes. The total days are counted on the real calendar, so every February 29 in the span is included.

      Related calculators

      Birthday CalculatorDays to your next birthday, the weekday, and fun milestones.Days Between Dates CalculatorDays, weeks, months and business days between two dates.Day of the Week CalculatorWhat day of the week was — or will be — any date?Days Until CalculatorCountdown in days to Christmas, a holiday or any date.