Ethiopia has a different calendar which contains 12 months with 30 days and 13th month with 5 days which turns to 6 every four years.
This calendar give you most of the things you want, some of them are
1 - Mark today when you open it [Your computer date must be correct in Gregorians']
2 - Display both Ethiopian and Gregorian date when you hover to each day
3 - Mark Ethiopian National days, Christian Holidays and (Muslim Holidays in approximation starting from 1988 EC)
4 - It can take you to the day you want by entering complete Ethiopian day
5 - Convert both ways (From Ethiopian to Gregorian and vice versa)
6 - It displays national events and holidays in one page and navigates you to exact day to the calendar
You will find it very useful once you start using it and simplify your calendar need for 150 years starting from 1900 - 2050.
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