Add or Subtract Days from a Date
days
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Formula: Result = Start Date + N days
Add/Subtract Days Calculator
This calculator adds or subtracts a number of days from any date, handling month boundaries and leap years.
Conversion Formula
Result = Start Date + N days
JavaScript's Date.setDate() handles month and year rollovers automatically.
Step-by-Step Examples
Jan 1, 2024 + 90 days = March 31, 2024
31+29+31=91, so 90 days = March 31 (leap year)
Mar 15, 2024 - 30 days = February 14, 2024
30 days back from March 15
Frequently Asked Questions
Can I subtract days?
Yes, enter a negative number. For example, -30 subtracts 30 days from the start date.
Does this handle month boundaries?
Yes, adding 15 days to January 25 correctly gives February 9.
What about leap years?
Adding days through February 29 in a leap year is handled automatically.