Date Add Calculator
Add days, weeks, months, or years to any date and get the resulting date — handles month-end clamping correctly.
Result
Result
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How to use this calculator
- Pick the base date.
- Enter how many days, weeks, months, or years to add. Use a negative number to go backwards.
- Read the resulting date plus the day of the week it lands on.
About this calculator
Adding to a date sounds simple but has gotchas — Jan 31 + 1 month is February 28 or 29, not "Feb 31". This calculator follows the standard "clamp the day-of-month" rule used by date libraries, and shows the resulting day of the week along with the absolute day count for sanity-checking.
Frequently asked
You get Feb 28 (or Feb 29 in a leap year). The calculator clamps the day-of-month to the last valid day of the target month. Adding another month gets you Mar 28 (or 29) — note that month-add is not the inverse of itself when day clamping kicks in.
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