How old are you, exactly?
Most of us know our age in years and go vague after that. This calculator is exact: give it a birth date and a date to measure at (today by default on this page's example) and it returns your age in years, months and days — plus your life in total days, weeks, hours and minutes, the weekday you were born, and when your next birthday lands and how old you will turn. The "age at" date can be moved anywhere, so the same tool answers "how old was I when I graduated?", "how old will my daughter be when she starts school?" and "how old was that building when it was renovated?".
How age is counted
The breakdown is computed calendrically, not by dividing total days by 365.25: subtract the years first, then count whole calendar months forward, then the days left over. That is why the months and days figures always feel right — someone born on January 31 measures one month old on February 28 (clamped to the month's last day), not after some fixed 30.44-day "average month". Total days is a pure day count between the two dates, leap days included, so both views are available and always agree.
The February 29 question
People born on February 29 have their legal and everyday birthday on February 28 (or March 1, by some conventions) in non-leap years. This calculator uses February 28 for the "next birthday" projection in non-leap years, and the real February 29 when it exists, so a leap-day baby's "official" birthdays and true quadrennial birthdays are both visible across the five-birthday table below.
Worked example
Born October 12, 2000, on October 12, 2026 you turn exactly 26 years old — 9,496 days lived, born on a Thursday, with the next birthday (27) on Tuesday, October 12, 2027.
How to use this calculator
- Enter the date of birth.
- Enter the date to measure the age at — today, or any past or future date.
- Read the exact age in the green panel.
- Check the table for total days lived and the next birthday, and the five-birthday table below.
Why total days feels huge — and milestones worth celebrating
A 26-year-old has already lived nearly nine and a half thousand days. Round day-counts make charming alternative birthdays: your 10,000th day alive arrives at about age 27 years 5 months, and your 1,000th week at about 19 years 2 months. To find the exact date of your 10,000th day, put your birth date into the Date Calculator and add 10,000 days.