Main Window
This is the start-up view. Click "Get random date" to select a date, or type a date into the adjacent box. Then enter a weekday, Sunday to Saturday, below the date. Click "Check answer".
Showing a Correct Answer
Here the options have been changed to include dates from the year 1 BC to the year 2799. The weekday entered is correct.
Showing an Incorrect Answer
Incorrect answers are shown in red. To see the correct answer, click "Show true answer".
Show Working Clicked
Click "Show working" to show exactly how the correct answer was calculated.
About the Far Future
If you choose a date in the far future, a warning appears about the accuracy of the Doomsday method.