Today, Monday April 1, is the "official" Sizdah Bedar in Iran... although most Iranians living outside Iran celebrate the holiday on the closest Sunday (weekend) so that families and friends can get easily get together without any work obligations.
Keep in mind that the time zone in Iran is GMT+3:30.
https://www.timeanddate.com/time/zone/iran
Also, since I mentioned Sunday is the weekend in many places outside of Iran, I want to add that the weekend in Iran is Friday and some companies work only half the day on Thursdays. This makes Saturday the first day of the work week in Iran.
I realize this may seem confusing to many non Iranians.
This said, I believe Americans' calendar, in terms of designating Saturday and Sunday as the weekend, is far more confusing since the American official calendar begins with Sunday and yet Americans call Saturday and Sunday the weekend — the weekEND. Analyze that!
