Date Add & Subtract Calculator
Start from any date, then add or subtract days, weeks, months or years to find the resulting date — and the day of the week it falls on.
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Frequently asked questions
How does adding months work for end-of-month dates?
If adding or subtracting months lands on a day that doesn't exist in the target month (for example, 31 January plus one month), the result is clamped to the last day of that month (28 or 29 February). This matches how most calendars and spreadsheets behave.
Does adding years handle leap days?
Yes. Adding one year to 29 February gives 28 February in a common year, and 29 February when the target year is also a leap year.
Can I subtract instead of add?
Yes — switch the operation to "Subtract" to move backwards in time by the chosen number of days, weeks, months or years.
What's the difference between adding 7 days and adding 1 week?
Nothing — one week is exactly seven days, so both give the same result. Weeks are offered as a convenience.