Crunch Age Calculator
Get your exact age down to the day — plus total days lived, the weekday you were born, and a countdown to your next birthday.
| Total days lived | 0 |
| Day of the week born | — |
| Next birthday | — |
| Days until next birthday | 0 |
How it works
Age is computed by comparing calendar dates, borrowing months and days where needed — the same way official records do it. Leap years are handled automatically because the math uses real calendar months, including February 29 birthdays (which celebrate on February 28 or March 1 in non-leap years, depending on local custom).
Formula & worked example
Formula: Age = target date − birth date, worked out by calendar borrowing: subtract the days first (borrowing the length of the previous month when needed), then the months (borrowing 12 from the year), then the years.
Worked example: Born on Saturday, 10 March 1990? On 24 June 2026 you are exactly 36 years, 3 months and 14 days old.
Frequently asked questions
How is exact age calculated?
Subtract the birth date from today's date: full years first, then remaining months, then days. If today's day-of-month is earlier than your birth day, a month is borrowed — just like subtraction in school.
What about leap years?
They're built in. Someone born on February 29, 2000 is legally a year older on February 28 or March 1 in non-leap years (it varies by jurisdiction); this calculator counts from the calendar date directly.
Why would I need my exact age?
Benefits eligibility, retirement planning, insurance quotes, school enrollment cutoffs, and milestone birthdays (18, 21, 65) all depend on exact age — "about 40" isn't precise enough for paperwork.