Age Calculator
Find your exact age in years, months, and days. Includes total days, weeks, hours, and days until your next birthday.
Date of birth
Your age
36 years, 5 months, 2 days
Next birthday in 212 days.
Total days
13,302
Total weeks
1,900
Total months
437
Total hours
319,248
Frequently Asked Questions about the Age Calculator
How is age calculated?
We compare your birthday to today's date, subtract the years, then adjust months and days. Leap years and varying month lengths are accounted for. The result is your exact age in years, months, and days.
Why is my age different from other calculators?
Different calculators round differently. Some show only years, some count partial days as full days, some ignore leap years. This calculator does the strict calendar arithmetic that matches how a human would count.
Does this calculator handle leap years?
Yes. JavaScript's Date object handles leap years correctly, including the once-per-400-years exception. If you were born on February 29, your age increments on March 1 in non-leap years (by US legal convention).
How many days until my next birthday?
We show that directly. If your birthday is today, we count to next year's birthday. If your birthday is in February 29 and the next year is not a leap year, we count to March 1 of the next non-leap year (US default).
Why are months and days both shown alongside years?
Because age is more useful than just a whole number for babies, milestones, and exact records. A 6-month-old child is described as such, not as 0 years old.
Can I check my age on a future date?
The current version uses today's date. We will add a 'as of' date input in the next update.