日付電卓 for PC

This "Simple is BEST!" Date calculation app wanted.
 
Is something similar app there are several, but may not correspond to the Japanese, such as not a simple than how to use thought, did not meet the app reminiscent to try to install in the trial.
 
Calculation the following only two possible with this "date calculator".
- To calculate the date of the previous or the number of days after the specified number of days from the specified date
- To calculate the number of days, number of months until the specified date from the specified date
 
Usage is very simple!
From among the three items to select and enter the two items automatically calculates the one item that remains.
 
With this "date calculator", simple to this calculation ...
- August 15, 2016 flight of the release date of "Early Bird 75" is?
→ to date 1 "August 15, 2016", just type "-75" date on the number of days.
• The payment completion Once you crossed the 240 months of the split loan to January 1, 2016?
→ to date 1 "January 1, 2016", just type "240" months in number of months.
How many days - from his birthday until today?
→ to date 1 "birthday", only to set the "today's date" to date 2.
 
※ on DatePicker constraints of Android, 1 January previous date 1900 can not be correctly calculated and displayed.
※ constraints on, numerical value that can be entered in the number of days or months or years of Java is limited to -2147483648 to 2147483647.