📅 Date Calculator

To calculate days between two dates, our calculator subtracts the start date from the end date and counts all days in between. The calculation accounts for leap years, different month lengths, and can include or exclude the end date based on your preference. Simply enter both dates and click calculate.

To add days to a date, go to the "Add/Subtract Days" tab, enter your starting date, select "Add" as the operation, and enter the number of days you want to add. The calculator will show you the resulting date along with the day of the week and other useful information.

Use our Age Calculator tab to find out exactly how many days old you are. Enter your birthdate, and the calculator will show your age in years, months, weeks, days, and even hours. It also shows when your next birthday is and how many days until then.

Yes! Our date calculator automatically accounts for leap years when calculating date differences or adding/subtracting time periods. Leap years occur every 4 years (with exceptions for century years), and our calculator handles all these rules correctly to ensure accurate results.

Our calculator supports multiple date formats including MM/DD/YYYY (US format), DD/MM/YYYY (European format), YYYY-MM-DD (ISO format), and DD MMM YYYY (e.g., 15 Jan 2024). You can change the display format in the settings section without affecting the accuracy of calculations.

Yes! When calculating days between dates, our calculator automatically shows both the total days and the number of business days (weekdays only, excluding weekends). This is particularly useful for project planning, work schedules, and business deadline calculations.