Age calculator
Exact age in years, months and days.
About this calculator
Enter a date of birth to see an exact age today, or change the second date to find the age on any other day.
You also get the total number of days and weeks, and the day of the week the person was born.
How it works
Counts whole years, then whole months, then the days left over on the calendar.
The story behind it
Working out an exact age is harder than it sounds, because months have different lengths and leap years come and go. Even the rules differ by country: South Korea moved its legal and administrative age counting to the international system only in June 2023. This calculator uses the common method: whole years, then whole months, then the days left over.
Why you can trust this calculator
- It runs in your browser. Nothing you type into it is sent anywhere.
- The method is explained on this page, so you can check it yourself.
- Free to use, with no sign-up.
- Results are estimates, so please double-check anything important.
- Spotted a mistake? Tell us and we'll look into it.
After 15 years as a mathematics educator, I built CalculStore to give students, teachers, professionals and anyone working with numbers simple, reliable tools.
Meet the founder