Age Calculator

The age calculator takes your birth date and an optional target date (defaults to today if left unchanged). It computes the full difference in years, months, and days by counting calendar months and adjusting for partial months. The total months, weeks, and days are also shown so you can express age in whichever unit is most useful.

For example, if someone was born on March 15, 1990 and today is July 22, 2026, the calculator reports 36 years, 4 months, and 7 days. It would also show that is 436 months, about 1,896 weeks, and 13,278 total days old. These alternative views are helpful for medical contexts (age in months for infants), fitness planning (age in weeks), or just satisfying curiosity.

Why count age in different units?

Different situations call for different age units. Pediatricians track infant development in months. Some fitness programs organize training by weekly age. Tracking total days lived can add perspective to life planning and goal setting. The calculator gives all three views so you do not need separate tools.

Birthday countdown and zodiac

The calculator shows how many days remain until your next birthday and the exact date it falls on. It also shows your zodiac sign based on the birth month and day — a fun detail that many people enjoy alongside the core age calculation.

Is the calculation exact?

The calculator uses calendar date arithmetic, not a simple 365-day year approximation. It accounts for leap years and varying month lengths. The years-months-days result matches the way people normally think about age (you turn one year older on your birthday each year). The total-day count is a precise difference between the two dates. If you need age down to hours or minutes, a date-of-birth calculator is a starting point, but this tool focuses on calendar-day precision.