Date Add Calculator
Add or subtract days, weeks, months or years from a date.
Frequently Asked Questions
How does adding months handle short months?
JavaScript date arithmetic rolls over: adding one month to 31 January gives 3 March in a non-leap year, because February has no 31st. This matches how most calendar software behaves.
Can I subtract dates too?
Yes. Choose Subtract as the direction and the amount is taken away from the start date. The tool always reports the total number of calendar days between the two dates.
Are business days counted?
No, this tool works with calendar days including weekends. Use the Business Days Calculator when you need to skip Saturdays and Sundays.
Is the Date Add Calculator free, and is my data private?
Yes. It is completely free and every calculation runs locally in your browser, so the numbers and dates you enter are never uploaded, stored, or shared with anyone.
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