PVN - The Event Date Difference Calculator Page

The Event Date Difference Calculator

(Click the image at any time to return to the initial view).

Click here to go to the download page...

The Calculator

The Event Date Difference Calculator tells you how much time elapses between two Events, which can be specified either manually in the START/FINISH date fields, or by choosing an Event from the Event List via the File menu. For example, how much time elapsed between the attack on Pearl Harbor and the end of World War II? ... Or suppose you were born on March 14, 1984 at 8:37 a.m. How old are you at this exact moment?


  • Choose a Start Date and Time by selecting a Month, Day, and entering a Year. Optionally set a start time (in hours, minutes, and seconds).
  • To use the current date/time, click the Use Current Date/Time box. Dates between January 1, A.D. 0 and December 31, A.D. 9999 are supported.
  • Choose a corresponding Finish Date and Time. Then click the Calculate button.

The Event Calculator comes with a set of pre-defined Events.

  • To choose a pre-defined event, click the File menu, then select Load Start Calendar. Click on the desired event, then the Select button.
  • Click the Close button on the Event List window to return to the Event Calculator.
  • Select a predefined Finish event in the same way, by selecting Load Finish Calendar, and clicking on the desired event in the Event Window.
  • Click the Calculate button to determine the event date difference.


For Java developers, I wrote Some Notes on Developing a JavaFX Application.

Known Issues

  • The Time Zone field has not been implemented yet; all dates are calculated based on Greenwich Meridian Time (GMT).
  • No consideration has been given to Daylight Savings Time. Leap Years are modeled correctly, but Leap Seconds have not been accommodated.
  • The Julian-Gregorian cut-over date is fixed at Oct 4, 1582. In reality, many countries implemented the cutover at later dates. The ability to model different cut-over dates is not currently modeled.

Comments, New Bugs, etc.

Please direct your comments, bug findings, etc. to me at pnau@san.rr.com