Date Addition & Subtraction Engine
Date Calculator
Add or subtract years, months, weeks, and days to or from any starting date. Instantly find future deadlines or past dates with weekday identification.
Resulting Target Date
Tuesday, September 08, 2026
Day of Week:
Tuesday
Elapsed Duration:
45 Days
Date Calculator FAQs
When adding a month to a date like January 31, if the target month has fewer days (like February), the calculator adjusts to the last valid day of that month (e.g., February 28 or 29).
Yes! Simply select the 'Subtract' mode, enter the number of years, months, weeks, or days, and click calculate.
Yes, leap year rules are automatically applied whenever your date calculation crosses a leap day (February 29).
Elapsed duration is the total number of days between your original starting date and the newly calculated target date.
Absolutely. Entering your project start date and adding weeks or days provides your exact completion deadline.
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