Asia has 48 countries on this count, and the middle is where runs stall
China, Japan, India and the two Koreas come first, then most of South East Asia. The board tends to stall in two places. One is Central Asia: Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan, five neighbours whose names all end in stan and blur together easily. Afghanistan and Pakistan end in stan too, but the UN files both under Southern Asia. The other is the Gulf, where Bahrain, Qatar, Kuwait, Oman and the United Arab Emirates sit close enough on the map to swap places in memory.
The small island states go missing as well. The Maldives, Singapore and Bahrain share no land border with anyone, so no walk along a frontier ever hands them to you.
Which countries count as Asia here
The 48 are the countries the UN M49 geoscheme files under Asia, which is the convention this site and the Geography app use for every continent. Türkiye, Cyprus, Armenia, Georgia and Azerbaijan are counted as Asian, as is Kazakhstan, even though each has a foothold or a stake in Europe. Russia is not: the UN counts it in Europe in full, even though most of its land lies in Asia, so it is on the Europe countries quiz. Egypt is counted in Africa, Sinai included. Type any of them here and the quiz tells you which board it is on.
Palestine is on the board, as one of the two UN observer states in the 195 this site counts. Taiwan is not, because it is neither a UN member nor an observer, which is a statement about UN membership rather than about how Taiwan is governed. Is Taiwan a country? covers that in full, and how many countries are in Asia sets out why published totals run from 46 to 51.
Tricks that make the 48 stick
Work by region. The UN splits Asia into five: Western Asia has 18 countries, South-eastern Asia 11, Southern Asia 9, and Central Asia and Eastern Asia 5 each. Southern Asia holds the one surprise: the UN puts Iran there, not in Western Asia with its Gulf neighbours.
Western Asia is the big one, so split it again: the Gulf and Arabian Peninsula, Yemen included; Anatolia and the Levant, from Türkiye and Cyprus down to Jordan, with Iraq to the east; and the Caucasus three. The method is written out properly in how to remember every country in the world, and the capitals quiz, set to Asia, takes the same countries from the other side.