Dates & age
Age Calculator
How old am I? Enter your date of birth to instantly calculate your exact age in years, months, and days, plus total days lived and a countdown to your next birthday. Free, no sign-up.
How Age Is Calculated
Age is calculated by subtracting your date of birth from today's date. The result accounts for month length and leap years to give a precise breakdown in years, months, and days, not just a rounded number.
For example, if you were born on March 15, 1990 and today is March 18, 2026, your exact age is 36 years, 0 months, and 3 days, not simply 36.
Years
Full years since birth. Increases on your birthday each year.
Months
Remaining full months after counting full years. Resets to 0 on your birthday.
Days
Remaining days after counting full years and months. Accounts for varying month lengths.
Leap Years and February 29 Birthdays
Leap years (divisible by 4, with century exceptions) add an extra day, February 29, every 4 years. The calculator handles all leap years automatically. If you were born on February 29, your birthday is treated as March 1 in non-leap years for the "next birthday" countdown.
How the Next Birthday Countdown Works
The countdown builds a birthday date for the current year using your birth month and day, then compares it against today. If that date has already passed (or is today), the calculator moves it forward one year and counts the days from today until that future date.
This is why the countdown always shows a number between 0 and 366, never a negative value: as soon as one birthday passes, the calculator immediately starts counting toward the next one rather than showing days since the last birthday.
Common Use Cases
Accuracy Notes
Local date and time: The calculator reads today's date from your device's local clock, not a server. If you are checking your age right around midnight, results are based on your browser's local calendar day, which can differ from UTC.
Total days vs. calendar age: Total days lived is a raw count of 24-hour periods since birth, while the years/months/days breakdown follows the calendar (so a 1-year-old is not necessarily exactly 365 days old, since leap years can add a day).