How many major religions are there?

The answer, of course, depends on what counts as a major religion. Different commentators give different lists of major religions, usually without rationale. My own criterion is this: a religion counts as major so long as it enjoys more than 100 million followers today. My criterion is objective since it classifies every religion as either major, or not, without evaluating it for metaphysical cogency or moral attractiveness. Why do I select 100 million as the cut-off mark? Because the smallest major religion has way more than 100 million followers, while the largest minor religion has way fewer. There is thus a sizable gap between major and minor as I have defined these terms.

According to the 1997 World Almanac, there are 1900 million Christians, 1100 million Muslims, 1100 million atheist/agnostics, 780 million Hindus, 320 million Buddhists, 230 million Confucian/Taoists, and 270 million others, for a total of 5700 million human beings.

These numbers are highly suspicious, however. For one thing, the Almanac does not define religious affiliation. One suspects that different demographers in different parts of the world worked according to different criteria. For another thing, most Confucians and Taoists, most or many Buddhists, and a fair number of Hindus and others are atheists. How, then, can the numbers given add up to the total world population?

Nonetheless, from the information available, it's probably safe to say that there are six major religions.