Place Value Time for PC

Time Calculator Place Value Time elapsed or countdown between two dates
Paid version of nummolt's Time Calculator.

Visually explains the calculations made by the free nummòlt's 'time calculator' Math Cats app.

Year, month, day, hour, minute, second ordered like any other place value system.
But time is not a usual place value system.
Each year has the same number of months: 12.
But months have a different number of days.
January, March, May, July, August,October and December have 31 days.
April, June, September and November: 30.
February has a variable number of days depending on whether is in a leap year or not.
Most years that are multiples of 4 are leap years.
Years multiples of 100 that cannot be exactly divided by 400 are not leap years.
February in a normal year has 28 days.
February in a leap year has 29 days.
The day has 24 hours.
Each hour has 60 minutes.
Each minute has 60 seconds.

The program shows the difference between two dates.
The program executes the carry operation if necessary, and a red corner of the cells shows the difference in each place value box.

This app has been done due to the amount of questions and answers made over the years on the operation of Time Calculator in MathCats. I hope this visual explanation clarify any doubts that may arise.