1. What is Calendar Days Calculation?

The Calendar Days Between Dates calculation determines the exact number of days between two dates, including all days in the period (start date through end date).

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( \text{Date1} \) — The start date
• \( \text{Date2} \) — The end date

Explanation: The calculation counts all calendar days between the two dates, including both the start and end dates if they are included in the count.

3. Importance of Days Calculation

Details: Calculating days between dates is essential for project planning, legal matters, financial calculations, medical treatments, and many other applications where precise time measurement is required.

4. Using the Calculator

Tips: Enter both dates in the format YYYY-MM-DD. The calculator will automatically compute the number of calendar days between them.

5. Frequently Asked Questions (FAQ)

Q1: Does this include both start and end dates?
A: The calculation includes all days in the period. Whether to count the start/end date depends on your specific requirements.

Q2: How are leap years handled?
A: The calculation automatically accounts for leap years and varying month lengths.

Q3: What's the maximum date range this can handle?
A: The calculator can handle any valid date range supported by PHP's DateTime class (typically years 0-9999).

Q4: Can I calculate days excluding weekends?
A: This calculator counts all calendar days. For business days calculation, a different tool would be needed.

Q5: Does time of day affect the calculation?
A: No, this calculation is based on whole calendar days only.