What does this tool do?
Month arithmetic is awkward at month ends because 31 January plus one month does not exist in February. Choose whether to clamp to the last valid day or let the date roll into the next month.
The Formula
Result = start date with the month changed by N; the day is clamped to the target month lengthFrequently Asked Questions
What happens when I add one month to 31 January?
The target month has no 31st. With clamping the result is 28 or 29 February; with overflow it rolls into early March.
Can I subtract months?
Yes. Enter a negative number of months to move backwards by the same calendar logic.