Calculate your exact age in your browser
Enter a date of birth above and you immediately get the exact age in years, months and days, plus the total months, weeks and days lived and a countdown to the next birthday. The reference date defaults to today and can be set to any day. Everything runs locally — nothing is uploaded.
How is an exact age calculated?
Full years are counted first, then full calendar months, then the remaining days. Month ends are clamped: someone born on January 31 completes a month on the last day of February, so the result never shows impossible dates. A calendar year averages 365.2425 days in the Gregorian calendar — which is why "years × 365" is always slightly off and a proper calendar calculation is needed.
What the totals tell you
Besides the headline age, the calculator shows the lived time as total months, weeks and days. That's useful for milestones (a 10,000-day birthday comes at about 27.4 years), for official forms that ask for age in months for small children, and for deadlines defined in days.
Leap-year birthdays
Born on February 29? In non-leap years the next birthday is shown on March 1, following the German legal convention (§ 188 BGB analog): the year of life completes with the end of February 28. In leap years the real date is used.
Private by default
The date of birth is processed entirely on your device — no upload, no storage, no tracking. The tool also works offline.