Date arithmetic

Add or subtract dates

Move a date by calendar units. Years are applied first, then months, then weeks and days; invalid month-end dates clamp to that month’s final day.

Result

Monday, February 28, 1949

Added to Saturday, January 29, 1949.

ISO date1949-02-28

WeekdayMonday

Absolute day distance30

Month-end clamping happens after years and again after months. For example, subtracting one month from March 31 lands on February 28 or 29.