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Months from today

Month arithmetic clamps overflow. The rule is deterministic and the same across the site.

Documented overflow rule

31 January + 1 month → last day of February. 31 March + 1 month → 30 April. This matches common civil “same day number or last valid day” behavior, not “add 30 days.”

Questions

January 31 plus one month?

The result is 28 February, or 29 February in a leap year. The original day number is kept when the destination month is long enough.

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