Date & Time Calculators
Work out your exact age, the days between two dates, or count down to any moment that matters to you.
Age Calculator
Find your exact age in years, months, and days — plus fun stats and your next birthday.
Calculate →Date Difference Calculator
Find exactly how much time lies between two dates, in days, weeks, or months.
Calculate →Countdown Timer
Set a target date and watch a live countdown to days, hours, minutes, and seconds.
Calculate →Calculating dates in your head is particularly tricky, as month lengths vary and leap years disrupt any simple rule of thumb. These three tools — including an age calculator — handle the calculations for you.
Calculation Tools
- Age Calculator: your exact age in years, months, and days, as well as the date of your next birthday.
- Date Difference Calculator: the duration between two dates of your choice, expressed in days, weeks, or months.
- Countdown Timer: a real-time countdown to a target date, accurate to the second.
Why Date Calculations Are Complex
Months range from 28 to 31 days; consequently, the date corresponding to a “three-month” period varies depending on the start date. Leap years add an extra day every four years, except for century years that are not divisible by 400. In calculations spanning more than a few weeks, these irregularities compound, quickly rendering manual calculation (like counting on your fingers) ineffective.
These three tools correctly account for calendar rules—including leap years—ensuring an accurate result rather than just an estimate.