Date Calculator

Calculate days between dates and add or subtract days from any date

Start Date

End Date

Days Between

0

Weeks Between

0

Months Between

0

Years Between

0

Start Date Details

Date: Select a date

Day of Week: Select a date

Day of Year: 0

Week of Year: 0

Leap Year: No

End Date Details

Date: Select a date

Day of Week: Select a date

Day of Year: 0

Week of Year: 0

Leap Year: No

Note: Date calculations are based on the Gregorian calendar. Month calculations use an average of 30.44 days per month, and year calculations use 365.25 days per year for leap year adjustments.

Features

  • Calculate days between two dates
  • Add or subtract days from a date
  • Get day of week and day of year
  • Check for leap years
  • Calculate weeks and months between dates

Common Uses

  • Project planning and deadlines
  • Event scheduling and countdowns
  • Age and anniversary calculations
  • Financial planning and interest calculations

Understanding Date Calculations

Date calculations involve working with the Gregorian calendar system, which accounts for:

  • Different month lengths (28-31 days)
  • Leap years (every 4 years, except for years divisible by 100 but not by 400)
  • Week and day numbering systems

The calculator handles these complexities automatically, providing accurate results for:

  • Days between dates (including leap years)
  • Adding or subtracting days (accounting for month lengths)
  • Day of week and day of year calculations
  • Week of year calculations

FAQ

How do I calculate days between dates?

Enter the start date and end date. The calculator will show the number of days, weeks, months, and years between them.

How do I add or subtract days from a date?

Enter the start date, select "Add" or "Subtract", and enter the number of days. The calculator will show the resulting date and its details.

How are leap years handled?

The calculator automatically accounts for leap years in all calculations. A year is a leap year if it's divisible by 4, except for years divisible by 100 but not by 400.