Age Calculator
Enter a date of birth to get an exact age breakdown — no rounding, no guessing how many days are in each month.
Overview
Age in years alone hides a lot of detail — two people born a year apart in years but 11 months apart in actual time both round to "1 year old" if you're not counting carefully. This calculator does the full calendar math: it counts complete years, then complete months within the remaining time, then the leftover days, so the result reflects actual elapsed calendar time rather than a rough subtraction of birth year from current year.
Examples
Age as of today
Born 1990-06-15, as of 2026-08-15
36 years, 2 months, 0 days
Age as of a specific date
Born 2000-01-01, as of 2026-08-15
26 years, 7 months, 14 days
How It Works
- Enter the date of birth.
- Optionally enter a different "calculate age as of" date — leave it blank to use today.
- The exact age in years, months, and days appears instantly, along with the total number of days lived.
Use Cases
Eligibility checks
Confirm whether someone meets an exact age cutoff for a form, exam, or membership rule.
Milestone tracking
Find out exactly how many days old a child or a milestone anniversary is.
Tips
- The "as of" date can be in the past — the calculator will happily compute an age as of any historical date, not just today.
FAQ
No. The calculation runs entirely in your browser using JavaScript — nothing is transmitted anywhere.
It counts full calendar months elapsed, then the remaining days against the day-of-month in the most recent month boundary, so results stay accurate across months of different lengths and leap years.
No — the tool will show an error, since a negative age isn't meaningful.