Ramadan guides
The countdown answers when. These answer how it is decided, and by whom, for Malaysia, Singapore, Brunei, Indonesia, Saudi Arabia and Turkey.
How the start of Ramadan is decided Rukyah, hisab and the MABIMS criterion of 3 degrees and 6.4 degrees, and why Malaysia, Singapore and Brunei could in principle start on different days. When Ramadan ends and 1 Syawal begins The date of 1 Syawal, why a month runs 29 or 30 days, and why the JAKIM takwim and Umm al-Qura part company by one day at the close.
Every date on this site is labelled projected until the responsible authority announces it. See about 1Ramadan for where the dates come from.