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.
Monday, October 27, 1975
Added to Saturday, September 27, 1975.
ISO date1975-10-27
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.