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Age Calculator

Calculate exact age in years, months and days from a date of birth.

Calculate exact age in years, months and days as of today.

Result

How to Use

  1. Enter your date of birth using the date picker.
  2. The result updates instantly, calculated as of today.
  3. The result also shows your total age in days and weeks.
  4. Use Copy Result to copy the answer to your clipboard.

Formula

age = (today − date_of_birth), broken into whole years, whole months, and remaining days

Worked Example

Someone born January 1, 2000, as of June 15, 2024.

  1. Whole years elapsed since 2000-01-01: 24 (the next birthday, 2024-01-01, has already passed).
  2. Whole months elapsed since the most recent birthday (2024-01-01) to 2024-06-15: 5 full months, reaching 2024-06-01.
  3. Remaining days from 2024-06-01 to 2024-06-15: 14 days.
  4. Total days elapsed since 2000-01-01: 8,932 days (1,276 weeks).

Result: 24 years, 5 months, 14 days (8,932 days total, 1,276 weeks)

About This Tool

What this tool does

This calculator finds the exact age between a date of birth and today, expressed as a precise years/months/days breakdown, plus the total number of days and weeks that have elapsed.

When to use it

Use it to find someone's exact current age, to check eligibility rules that depend on an exact age (not just a birth year), or to find out how many days or weeks someone has been alive.

What the result means

The years/months/days figure is the precise calendar age as of today. The total days/weeks figure is the same span of time expressed as a single running count, which is useful for things a "years old" figure can't answer, like exact day counts for anniversaries or milestones.

Assumptions & limitations

A date of birth after today is rejected as invalid, since a person cannot be born in the future. For a birthday on February 29, this calculator treats the birthday as completing a year on February 28 in non-leap years — the same convention used by most calendar software and several jurisdictions' legal definitions — rather than delaying it to March 1.

Frequently Asked Questions

How is exact age calculated?
By comparing the date of birth to today's date and counting whole years, whole months, and remaining days — the same way you'd count on a calendar, not just subtracting years.
What happens to a February 29 birthday in a non-leap year?
It's treated as falling on February 28 for the purpose of completing a year of age, since February 29 doesn't exist that year. On February 29 itself (in a leap year), the birthday lands exactly as expected.
Why does it show total days and weeks as well as years/months/days?
Some uses need a single running number rather than a breakdown — for example, "how many days old" milestones, or comparing exact spans of time. Both figures come from the same calculation, so they always agree.