Date & Time Tool

Date Calculator

Add or subtract time from dates, or calculate the difference between two dates

Date Calculation

Ready to Calculate

Select a mode and enter your dates to get started

About Date Calculations

Adding and Subtracting Dates

When adding or subtracting time from dates, the calculator accounts for varying month lengths, leap years, and other calendar irregularities. For example, adding one month to January 31st gives you February 28th (or 29th in leap years) since February doesn't have 31 days.

Calculating Date Differences

The difference between two dates can be expressed in multiple ways. The calculator provides both the breakdown (years, months, days) and the total in single units (days, weeks, hours). This is useful for different contexts - legal documents might need exact years and months, while project planning might need total days.

Practical Applications

Date calculators are invaluable for project management, determining due dates, calculating age or tenure, planning events, tracking warranty periods, calculating loan terms, and many other real-world scenarios where precise date arithmetic is needed.

Business vs Calendar Days

Note that this calculator counts all calendar days, including weekends and holidays. For business day calculations (Monday through Friday only), you would need to account for these separately based on your specific requirements and locale.