Date Calculator
Add or subtract days, weeks, months, or years from any date to find a future or past date. Handles leap years correctly — useful for deadlines, scheduling, and date math.
Result
2026-06-19
How to use the date calculator
Pick a starting date and how many days/months/years to add (use negatives to subtract).
Formula & explanation
Adds in this order: years, then months, then days, using JavaScript Date arithmetic which handles month-overflow.
Examples
2024-01-31 + 1 month = 2024-03-02 (Feb has only 29 days in 2024).
Frequently asked questions
- How do I subtract days from a date?
- Enter a negative number in the Days field. For example, -7 subtracts one week from the starting date.
- What happens when adding a month to January 31?
- February doesn't have 31 days, so the result overflows to March 2 or 3 depending on whether it's a leap year. This matches standard calendar arithmetic used by most date libraries.
- Does this account for leap years?
- Yes — the browser's native Date object correctly handles leap years, so February 28 + 1 day = February 29 in a leap year.
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