Date Calculator

Calculate days between dates, add or subtract days from a date, and find future or past dates.

Days Difference

0 days

Weeks

0 weeks

Months

0 months

Years

0 years

Date Difference Details

Start Date:April 28, 2025
End Date:April 28, 2025
Total Days:0 days
Total Weeks:0 weeks and 0 days
Total Months:0 months
Total Years:0 years and 0 months

How to Calculate Days Between Dates

To calculate the number of days between two dates, our calculator:

  1. Converts both dates to milliseconds since January 1, 1970
  2. Finds the absolute difference between these values
  3. Divides by the number of milliseconds in a day (86,400,000)
  4. Rounds up to the nearest whole number

Understanding Date Calculations

Date calculations are essential for many personal and professional tasks, from planning projects to calculating age or determining payment periods. Our date calculator provides several useful functions to help you work with dates efficiently.

Types of Date Calculations

Days Between Dates

Calculating the number of days between two dates is useful for determining durations, planning projects, or calculating age. The calculation includes both the start date and end date in the total.

Adding or Subtracting Days

When you need to find a future or past date based on a specific number of days from a reference date, you can add or subtract days. This is useful for:

  • Determining due dates
  • Planning project milestones
  • Calculating warranty expiration dates
  • Finding payment deadlines

Working Days Calculation

For business purposes, it's often necessary to calculate working days between dates, excluding weekends and holidays. This is important for:

  • Project planning
  • Delivery estimates
  • Contract terms
  • Business processing times

Date Formats Around the World

Different regions use different date formats, which can sometimes lead to confusion:

  • MM/DD/YYYY: Commonly used in the United States
  • DD/MM/YYYY: Used in most European countries and many other parts of the world
  • YYYY-MM-DD: The international standard (ISO 8601) format

Our calculator uses your browser's locale settings to display dates in your preferred format, but internally processes dates in a standardized way to ensure accurate calculations.

Leap Years and Date Calculations

Leap years add an extra day (February 29) to the calendar and occur.