Age Calculator
Enter a birth date to calculate age on the reference date.
Find out precisely how many years, months, and days old someone is on a given date. Enter the birth date and a reference date (defaults to today). The calculator counts completed periods the way people usually describe age and also reports total days and weeks. Everything runs in your browser.
How to use
- Enter the birth date in the first field.
- The reference date defaults to today. Change it to see age on a past or future date.
- Read the breakdown in years, months, and days, plus the totals.
- Use Copy result for a compact summary, or Reset to start over.
Examples
- Born 1990-01-15, reference 2024-06-06: 34 years, 4 months, 22 days (12,561 total days).
- Born on a leap day 2020-02-29, reference the following Feb 28: 0 years, 11 months, 30 days (the birthday has not yet occurred in the non-leap year).
- Same date for birth and reference: 0 years, 0 months, 0 days.
FAQs
- How does the calculator handle leap days?
- A person born on February 29 is treated as having a birthday on February 28 in non-leap years for age purposes. This matches common real world counting so that the year does not increment until the equivalent day has passed.
- What does completed years, months, and days mean?
- It shows the largest whole number of years that have passed, then the largest whole number of additional months, then the remaining days. This is the way most people state their age or a child's age.
- Can I calculate age on a future date?
- Yes. Set the reference date after the birth date to project forward. The math is the same.
- Does it account for time of day?
- No. The tool works with whole calendar dates only. It counts the number of midnights that have passed between the two dates.
- Is my data sent anywhere?
- No. All calculations happen locally in your browser. The dates you enter never leave your device.
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