Age Calculator
Find an exact age from a birth date — in years, months, and days — plus totals and the next birthday.
Age Calculator calculates in your browser.
Find an exact age
Whether you need an age for a form, a school or sports cutoff, or you’re just curious how many days you have been alive, enter the birth date and the calculator shows the age in completed years and exactly — in years, months, and days — along with total months, weeks, and days and the next birthday. “Age as of” starts at today; change it to find an age on any other date. It works out chronological age on the calendar only.
How to use the Age Calculator
- Choose the birth date.
- Leave “Age as of” on today, or pick another date. The Today button switches back.
- Read the age, the exact breakdown, the totals, and the next birthday. Copy Result copies a one-line summary.
The method
age = completed years since the birth date
exact age = whole years, then whole months, then the remaining days
total days = calendar days from the birth date to the “as of” date
Age is counted on the calendar, not by dividing days by 365.25. The calculator steps forward from the birth date by whole years to the most recent birthday, then by whole months, and counts the days left over. Two rules keep this exact: a February 29 birthday falls on February 28 in years without a leap day, and a month that is too short for the birth day ends on its last day.
| Born | Age on | Exact age | Total days |
|---|---|---|---|
| March 14, 1987 | September 27, 2026 | 39 years, 6 months, 13 days | 14,442 days |
| February 29, 2000 | February 28, 2025 | 25 years | 9,131 days |
| January 31, 1990 | February 28, 2026 | 36 years, 1 month | 13,177 days |
| March 14, 1987 | March 13, 2026 | 38 years, 11 months, 27 days | 14,244 days |
| January 15, 2026 | September 27, 2026 | 8 months, 12 days | 255 days |
Calculated on your device
- The age is calculated in your browser; the birth date is never sent to Looty Tools or stored.
- The calculator area is masked from session-recording analytics, so the birth date and age aren’t captured in recordings.
- Refreshing the page clears the birth date.
Limitations
- February 29 birthdays are counted on February 28 in years without a leap day. Some legal rules use March 1 instead.
- It measures calendar age only — no time of birth or time zones, and no health or biological age.
- Dates use today’s Gregorian calendar for every year, including dates before it was adopted.
- The birth date must be on or before the “Age as of” date; years 1 to 9999.
Related calculators
- Date Difference CalculatorMeasure the span between two dates.
- Days Between Dates CalculatorCount the days from one date to another.
Guides
- How Age Is CalculatedHow completed years, months, and days are counted on the calendar, why dividing by 365.25 goes wrong, and how to check an age by hand.
- Leap-Day BirthdaysWhen someone born on February 29 turns a year older in other years, the February 28 and March 1 conventions, and how often a leap-day birthday comes around.
- Age in Years, Months, DaysWhat an exact age in years, months, and days means, why totals in months, weeks, and days don’t convert neatly, and where each form is used.
Age Calculator FAQ
- How is age calculated?
- Age is the number of completed years since the birth date. The exact age then counts whole months after the last birthday, then the remaining days, using real calendar dates — not 365-day years or 30-day months.
- How are February 29 birthdays handled?
- In years without a February 29, this calculator counts the birthday on February 28, the last day of February. Some legal systems use March 1 instead, so check the rule that applies if the exact day matters legally.
- Can I find someone’s age on a past or future date?
- Yes. “Age as of” starts at today, but you can choose any date on or after the birth date — for example, the age on a school cutoff date or on a future anniversary.
- Why isn’t the total number of days just years × 365?
- Leap years add an extra day roughly every four years. The total counts every actual calendar day between the two dates, so it is a little more than years × 365.
- How are months counted for birthdays on the 29th, 30th, or 31st?
- When a month is too short for the birth day, the month is counted as complete on that month’s last day. Someone born on January 31 is exactly 1 month old on February 28 (or 29).
- Does it calculate biological or health age?
- No. It calculates chronological age — the time since the birth date on the calendar — and nothing else.
- Is my birth date sent or saved anywhere?
- No. The age is calculated in your browser as you choose the dates. The birth date and results are not sent to Looty Tools or stored, and the calculator area is masked from session-recording analytics. Refreshing the page clears it.
