Question 1

How many days does December 1980 have?

Accepted Answer

December 1980 has 31 days. It starts on Monday and ends on Wednesday.

Question 2

What ISO week does December 1980 start in?

Accepted Answer

1 December 1980 falls in ISO week 49. Weeks run Monday–Sunday per ISO 8601.

Question 3

Where can I see the public holidays of Japan in December 1980?

Accepted Answer

The calendar on this page marks every national public holiday of Japan in December 1980 in red, with joint/regional days in amber.

12月 1980