FREE TOOL

Age Calculator

Find your exact age down to the day — plus fun stats about your time on Earth.

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years old
⏳ Countdown to Next Birthday

How Is Age Calculated?

Age is calculated by counting the number of complete years, months, and days between your date of birth and the target date. A full year passes when the same month and day arrive again. After counting full years, the remaining full months are tallied, and finally the leftover days round out the total.

Edge cases matter. If you were born on January 31 and today is February 28, the calculator recognises that February has no 31st — so you have not yet completed a full month since January 31. Similarly, if your birthday falls on the last day of a month, the tool checks whether the "as of" month is shorter before awarding a full month.

Leap-year birthdays add another wrinkle. If you were born on February 29, your birthday technically does not exist in three out of four years. This calculator counts a full year on March 1 in non-leap years, which is the most widely used legal convention. In a leap year, your actual birthday is used.

Fun Age Facts

🐶
Dog Years
Enter your birth date to see your age in dog years.
💓
Heartbeats
Your heart beats roughly 100,000 times a day.
🌬️
Breaths
An average person takes about 22,000 breaths per day.
🌍
Earth Orbits
Each year you complete one full orbit around the Sun.
🌙
Moon Cycles
The Moon completes a cycle roughly every 29.53 days.

Frequently Asked Questions

Enter your date of birth above and click "Calculate." The stats grid will show your total days alive. The number is computed by counting every calendar day from your birth date up to (and including) the target date.
After you calculate your age, one of the stats cards will display your birth weekday — for example "Wednesday." This is derived directly from the calendar and is always accurate for any date in the Gregorian calendar.
After subtracting full years, the calculator counts forward month by month from the resulting date. A month is "full" when the same day-of-month (or the last day of a shorter month) is reached. The leftover days after full months are reported separately.
Leap-day babies still age one year every 365 (or 366) days. In non-leap years, the calculator treats March 1 as the anniversary, following the most common legal convention. Your next-birthday countdown will point to February 29 in the next leap year or March 1 otherwise.
The calculator is accurate to the exact calendar day. All arithmetic runs locally in your browser using JavaScript's built-in date handling, which correctly accounts for leap years, varying month lengths, and daylight-saving shifts. No data is sent to any server.