CalcHub
Add or Subtract Dates
Add or subtract days, weeks, months or years to a date.
Result = date + amount × unit. Month and year additions clamp to the last valid day of the target month (Jan 31 + 1 month → Feb 28).
- Why does Jan 31 + 1 month give Feb 28?
- Months have different lengths, so the result clamps to the last valid day of the target month instead of overflowing into March.
- What about leap years?
- Feb 29 + 1 year becomes Feb 28 in a non-leap year. The calculator handles this automatically.
- Can I subtract dates?
- Yes — enter a negative amount, for example −30 days.
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