Adds calendar months rather than a fixed day count, correctly handling months of different lengths.
How it works
Six months are added to the start date’s month, with an end-of-month clamp — for example, May 31st plus 6 months correctly lands on November 30th rather than overflowing into December.
What this does not include
This does not include a fixed 180-day count — for that simpler day-based version, use this site’s 180-day calculator instead. This tool uses true calendar-month arithmetic.
How to use this calculator
- Enter the start date.
Frequently asked questions
Why is this different from the site’s 180-day calculator?
180 days and 6 calendar months aren’t always the same length — this calculator adds actual calendar months, correctly handling months with fewer than 30 or 31 days.
What happens when the start date doesn’t exist in the target month?
The date clamps down to the last valid day of that month — for example, January 31st plus 6 months lands on July 31st, but May 31st plus 6 months lands on November 30th.
Where is a 6-month window commonly used?
Warranty periods, probationary employment periods, and some visa or lease renewal windows.
