Age Calculator
Enter a date of birth. Add a second date to find someone’s age on that day.
How the calculation works
The calculator counts whole years first, then whole months, then the remaining days, borrowing from the previous month when needed, so month lengths and leap years are handled correctly instead of assuming every month has 30 days. The total-days figure is the number of calendar days between the two dates.
For someone born on February 29, the calculator treats March 1 as the birthday in years without a February 29. Legal rules differ by country, with some using February 28, so check local rules if the exact day matters.
Age milestones in days
| Days old | Age at that point |
|---|---|
| 1,000 | 2 years, 8 months |
| 5,000 | 13 years, 8 months |
| 10,000 | 27 years, 4 months |
| 15,000 | 41 years, 0 months |
| 20,000 | 54 years, 9 months |
| 25,000 | 68 years, 5 months |
| 30,000 | 82 years, 1 months |
| 1 billion seconds (11,574 days) | about 31.7 years |
To find the date of a milestone, enter your date of birth, then try dates in the second field until the total reaches the number you want.
When the exact age matters
Many rules depend on age on a specific date, not age today: school entry cutoffs, youth sports age groups, insurance and pension ages, and visa or license eligibility. Use the second date field to check age on that cutoff date.
Time zones
Dates are read in your device’s local time zone, so the result matches your own calendar. Someone in a time zone far from yours may see a birthday begin a day earlier or later.