1. What is Date Calculation?

Date calculation involves adding or subtracting a specific number of days from a given date to determine a new date. This is useful for project planning, medication schedules, financial calculations, and many other applications.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( date \) — The starting date
• \( delta \) — Number of days to add (positive) or subtract (negative)
• \( new\_date \) — The resulting date after calculation

Explanation: The calculator properly handles month boundaries, leap years, and all calendar variations when performing date arithmetic.

3. Importance of Date Calculation

Details: Accurate date calculations are essential for financial planning, project management, medical treatment schedules, legal deadlines, and many time-sensitive applications.

4. Using the Calculator

Tips: Enter the starting date in YYYY-MM-DD format and the number of days to add (positive number) or subtract (negative number). The calculator will handle all calendar complexities automatically.

5. Frequently Asked Questions (FAQ)

Q1: Does this account for leap years?
A: Yes, the calculator properly handles leap years and all calendar variations.

Q2: What's the maximum/minimum number of days I can add/subtract?
A: The calculator can handle very large positive or negative values (billions of days), though extremely large values may exceed PHP's date handling limits.

Q3: Can I calculate months or years instead of days?
A: This calculator specifically works with days. For month/year calculations, a different approach would be needed.

Q4: What date format should I use?
A: Use the standard YYYY-MM-DD format (e.g., 2023-12-31 for December 31, 2023).

Q5: Does time of day affect the calculation?
A: No, this calculator works with whole days only. Time components are not considered in the calculation.