1. What is Calendar Days Calculation?

Calendar days calculation determines the total number of days between two dates, including all days in the period (start date, end date, and all days in between).

2. How Does the Calculator Work?

The calculator uses simple date arithmetic:

Where:

• End Date — The later date in the period
• Start Date — The earlier date in the period

Explanation: The calculation counts all calendar days between two dates, including weekends and holidays.

3. Importance of Day Calculation

Details: Calculating days between dates is essential for project planning, legal matters, financial calculations, and various administrative processes.

4. Using the Calculator

Tips: Enter both start and end dates in the format YYYY-MM-DD. The end date should be equal to or later than the start date for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: Does this count business days or calendar days?
A: This counts all calendar days, including weekends and holidays.

Q2: Is the end date included in the count?
A: Yes, the calculation includes both the start date and end date in the total.

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 100-9999).

Q4: How are leap years handled?
A: The calculation automatically accounts for leap years and varying month lengths.

Q5: Can I calculate days between BC/BCE dates?
A: No, this calculator only works with dates in the Common Era (AD/CE).