Age calculator
Exact age in years, months, and days — and a countdown to your next birthday.
How we count age
We count complete years first, then complete months from your last birth-month anniversary, then remaining days. Leap years are handled by the calendar itself — when February 29 lands inside the range, it gets counted naturally without a special case.
Why "total days" sometimes surprises you
The years/months/days breakdown rounds down at every level, which quietly hides leap days. The total-days counter sums them all back in, so it'll usually be a few days higher than years × 365. If you're 30 years old, you've lived through about 7 leap years, so your total days will be ~7 days more than a flat 30 × 365.
Looking for date math instead of age?
If you want the gap between two arbitrary dates (a project deadline, a wedding anniversary, a contract renewal), use the date-difference calculator instead. This page is purpose-built for "how old am I, exactly".
Day-of-week trivia
Once a year your birthday lands on the same day of the week as your birth — every 6 or 7 years for adults, depending on how leap years stack up. We show the day you were born and the day your next birthday lands, so you can plan accordingly.
Frequently asked questions
How do I calculate my exact age in days?
Count every day between your birth date and today, including leap days. Enter your birth date above and the calculator shows the total automatically.
Does the age calculator account for leap years?
Yes. The calculator uses the actual calendar, so every February 29 that falls within your lifespan is counted in the total days.