1. What is Date Duration?

Date duration is the amount of time between two dates, typically measured in days. It's useful for calculating time intervals in project planning, age calculation, and various time-based analyses.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( date1 \) — The earlier date
• \( date2 \) — The later date
• \( Duration \) — Result in days

Explanation: The calculator computes the exact number of days between two dates, including leap years and varying month lengths.

3. Importance of Date Duration Calculation

Details: Accurate date duration calculation is essential for project management, financial calculations, legal agreements, medical treatments, and many other time-sensitive applications.

4. Using the Calculator

Tips: Enter both dates in the format YYYY-MM-DD. The second date must be later than the first date to get a positive duration.

5. Frequently Asked Questions (FAQ)

Q1: Does this calculator account for leap years?
A: Yes, the calculation automatically accounts for leap years and varying month lengths.

Q2: Can I calculate duration in months or years?
A: This calculator provides results in days. For months or years, you would need a different calculation method.

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: Does time of day affect the calculation?
A: No, this calculator only considers the date portion, not the time of day.

Q5: Can I use this for historical dates?
A: Yes, as long as the dates are in the Gregorian calendar (adopted in 1582 in most countries).