Days Between Two Dates Calculator

Calculate the number of days between two dates. This calculator helps you determine the time difference between any two calendar dates.

Input Parameters

Calculation Results

Calculation Formula

Days = End Date - Start Date

Where:
Start Date: The initial date of the period
End Date: The final date of the period
Days: The number of days between the two dates

Result

0 days

Days Between Two Dates Calculator Usage Guide

Learn how to use the Days Between Two Dates Calculator and its working principles

How to Use This Calculator

  1. Enter the start date in the "Start Date" field using the date picker.
  2. Enter the end date in the "End Date" field using the date picker.
  3. Select the calculation direction (forward or backward).
  4. Click the "Calculate" button to determine the number of days between the two dates.
  5. The result will display the number of days and describe the date range.

Working Principle

This calculator works by calculating the time difference between two dates and converting that difference into days. The calculation uses JavaScript's Date object, which measures time in milliseconds since January 1, 1970.

The formula used is:

Days = |End Date - Start Date| / (1000 × 60 × 60 × 24)

Example Uses

  • Calculate the duration of a project by entering the start and end dates.
  • Determine how many days until an upcoming event or deadline.
  • Calculate the age of a person by entering their birth date and current date.
  • Find the time difference between two historical events.

Tips

  • For best results, use the date picker to select dates rather than typing them manually.
  • The calculator automatically handles leap years and different month lengths.
  • If you get an error message, make sure both dates are entered correctly.