What date format should I use?

Use YYYY-MM-DD (e.g. 2025-03-07). The calculator uses local time.

Can I use negative days?

Yes. Negative days subtract from the date.

Yes. JavaScript Date handles leap years and month boundaries.

Add or subtract days from a date to get a new date.

Date (YYYY-MM-DD)

Days to add (negative to subtract)

What date format should I use?: Use YYYY-MM-DD (e.g. 2025-03-07). The calculator uses local time.
Can I use negative days?: Yes. Negative days subtract from the date.
Does it handle leap years?: Yes. JavaScript Date handles leap years and month boundaries.

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