How it works
Move directly by the entered number of calendar months, preserving the original day where possible and clamping to the target month’s last day.
Input definitions
- Starting date
- A complete Gregorian calendar date.
- Signed whole calendar months
- Enter the value in the labeled unit.
A worked example
- Starting date
- 2024-01-31
- Signed whole calendar months
- 1
Assumptions & limits
Gregorian dates 0001–9999. Direct month shifting differs from repeatedly adding one month after a date has been clamped.
Sources & review
Maintained by AnsRio. Methods and examples use automated checks; this does not imply independent professional certification.
Method updated 2026-10-17. Content checked against the stated method and examples. Our verification approach.
Common questions
What happens when I add a month to January 31?
The date is clamped to the last day of February: February 28 in a common year or February 29 in a leap year. A direct two-month shift retains the original day and produces March 31.
Do daylight-saving changes affect calendar date results?
Date-only operations compare Gregorian calendar dates at UTC midnight. They do not count local elapsed hours. Timestamp operations require an explicit offset; individual tool assumptions state boundary rules.
How does the Add or subtract calendar months tool work?
Move directly by the entered number of calendar months, preserving the original day where possible and clamping to the target month’s last day.
What are the assumptions and limits of Add or subtract calendar months?
Gregorian dates 0001–9999. Direct month shifting differs from repeatedly adding one month after a date has been clamped.