How are month-ends handled?

Months are clamped to valid dates — for example, January 31 plus one month lands on February 28 (or 29 in a leap year).

Date Calculator

Add or subtract years, months, weeks, and days from a date to find the resulting date, its day of the week, and the total day offset.

How are month-ends handled?: Months are clamped to valid dates — for example, January 31 plus one month lands on February 28 (or 29 in a leap year).

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