Date Addition and Subtraction
Move a calendar date forwards or backwards by days, weeks, months or years.
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How to use this tool
- Enter a calendar date, unit and signed amount.
- Calculate the resulting date and weekday.
Things to know
- Month/year arithmetic clamps to the final valid day when needed, so January 31 plus one month becomes February 28 or 29.
- Calendar amount: -100,000 to 100,000 days/weeks/months/years. One arithmetic operation; output must fit years 0001-9999.
- Use no more than 200,000 characters across the input and settings.
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