Age Calculator

Enter the person's date of birth in the first field. If you leave the second date blank, the calculator uses today's date as the reference—your current age. To find age on a specific past or future date (for example, the first day of school or a policy effective date), set that date as the end date.

Results show years, months, and days separately. If you only need the total number of days between two dates, use our days-between-dates calculator as well—it complements this view for legal or contractual wording.

The calculator walks forward from the start date one calendar unit at a time. It adds full years until another year would pass the end date, then full months, then counts remaining days. That is why someone born on March 10 is not "one year older" until March 10 of the following year—not on January 1.

Age in days (often needed for forms) is simply the number of midnights between two dates, or equivalently the difference in absolute time divided by 24 hours. Leap years are included automatically when the library counts across February 29.

Use your birth date and today's date (or any end date). The total day span is the count of days from the first date up to but not including the second, depending on how your tool labels boundaries—our interface shows both structured age and can be cross-checked with the date-difference tool for a single day count if needed.

If you were born on a leap day, many legal systems treat March 1 as your birthday in non-leap years for age increments. Our calculator uses true calendar math between the dates you enter, so always confirm against local rules for licenses, voting, or contracts.

Date-only fields use calendar dates in your locale without time-of-day. If you need an instant precise to the hour (for example, international birth records), use a datetime-aware tool; for everyday age, date-only is standard.

• School enrollment: Confirm a child meets the district cutoff age on the first day of class.
• Insurance or retirement products: Verify attained age on the policy anniversary date.
• Milestones:Plan a party or gift for a "10,000 days old" style milestone using date difference plus this age view.

Set the start date to today and the end date to your next birthday, or use the date-difference calculator between today and the upcoming birthday. That gives you a clean day count for countdowns and reminders.