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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.

Frequently Asked Questions

How do I calculate my exact age?▾
Enter your date of birth in the field above. The calculator instantly shows your age in years, months, and days as of today. The calculation accounts for leap years and varying month lengths.
How is age calculated in years, months, and days?▾
The calculator subtracts your birth date from today. It borrows days from the previous month when needed (accounting for month length) and borrows months from the current year when the month difference is negative. This gives you a precise breakdown rather than just rounding to whole years.
How many days have I been alive?▾
The "Total days lived" stat shows the exact number of calendar days from your date of birth to today, including leap days. The result updates automatically when you enter your birth date.
How are leap years handled?▾
Leap years are handled automatically. The total days count uses JavaScript's Date object which accounts for all historical and future leap years. If your birthday is February 29, the next birthday is calculated as March 1 in non-leap years.
Does this tool store my date of birth?▾
No. The calculation runs entirely in your browser. Your date of birth is never sent to any server, stored, or logged anywhere.
Can I calculate someone else's age?▾
Yes — just enter their date of birth. The calculator works for any person born in the past. There is no restriction on the birth year.
What is the "days until next birthday" count?▾
This shows how many calendar days remain from today until your next birthday. If today is your birthday, it shows 🎂 Today! The next birthday is always calculated in the upcoming year.