Date Calculator

How to Use This Date Duration & Difference Tool

1. Choose between Add/Subtract days to a date, or Find the difference between two dates.
2. Enter the start date (and the days/months/years to add, or the end date).
3. The result shows the calculated date or the duration in multiple units.
4. Toggle "exclude weekends" to count only working days.

Date Calculator provides an accurate way to perform complex calendar math, from finding the total days between two events to projecting future deadlines. Date arithmetic is surprisingly complex: adding 1 month to January 31 should give February 28 (not March 3); subtracting 30 days from a date crosses month and year boundaries; and calculating working days must account for weekends. This date difference tool handles all of these scenarios correctly using a calendar-aware engine.

Calendar-Aware Time Duration Calculator

Adding calendar months with this utility respects month-end clamping: January 31 + 1 month = February 28 (or 29 in a leap year), never March 3. This business day calculator and calendar math tool returns results in multiple units: exact days, business days (Mon–Fri), weeks + days, months + days, and years + months + days. Whether you are using it to calculate days between dates for a project timeline or to add days to date for a contractual deadline, our tool ensures your scheduling is precise and error-free.

• Add or subtract days, weeks, months, and years from any date
• Find the difference between two dates in days, weeks, months, and years
• Business day calculation excludes weekends (Mon–Fri only)
• Handles leap years and month-end clamping correctly

See also the Days Until calculator, Countdown Timer, and Unix Timestamp Converter to build a complete scheduling workflow with this Date Calculator.