Major world religions have been distinguished from minor religions using a variety of methods, though any such division naturally reflects a particular bias, since many adherent of a religion are likely to consider their own faith "major". Two methods are mentioned in this article, number of adherents and the definitions used by classical scholars of religions.

For a list of all religions, please see the article List of religions.

Defined by population

One way to define a major religion is by the current number of current adherents. Population numbers by religion are computed by combination of census reports and population surveys (in countries where religion data is not collected in census, for example USA or France), but results can vary widely depending on the way questions are phrased, the definitions of religion used, and the bias of the agencies or organizations conducting the survey. Informal or unorganized religions are especially difficult to count.

All religions or belief systems by number of adherents

This listing does not draw distinctions between organized religion, which has a single belief code and religious hierarchies, and informal religions, such as Chinese traditional religions, which are a mix of different informal religious ideas.

1. Christianity 2 billion
   • Roman Catholicism: 1.1 billion
   • Protestantism: 360 million
   • Eastern Orthodoxy: 220 million
   • Anglicanism: 84 million
   • Other Christians: 280 million
2. Islam 1.3 billion
   • Sunnism: 940 million
   • Shiism 120 million
3. Hinduism 900 million
4. Secular/Nonreligious/Agnostic/Atheist 850 million
5. Buddhism 360 million
6. Chinese traditional religion 225 million
   • Not a single organized religion
7. Primal indigenous 150 million
   • Not a single organized religion
8. African Traditional and Diasporic 95 million
   • Not a single organized religion
9. Sikhism 23 million
10. Juche 19 million
    • Not considered a religion by adherents
11. Spiritism 14 million
    • Not a single organized religion
12. Judaism 14 million
13. Bahá'í Faith 6 million
14. Jainism 5 million
15. Shinto 4 million
16. Cao Dai 3 million
17. Tenrikyo 2.4 million
18. Neopaganism 1 million
19. Unitarian Universalism 800,000
20. Rastafarianism 700,000
21. Scientology 600,000
22. Zoroastrianism 150,000

• Source of statistics: adherents.com (http://www.adherents.com/Religions_By_Adherents.html)

Organized religions by population ranking

The Christian Science Monitor used a separate standard, examining only organized religions. The newspaper listed the following in 1998 as the "Top 10 Organized Religions in the World" based on descending level of population:

1. Christianity
2. Islam
3. Hinduism
4. Buddhism
5. Sikhism
6. Judaism
7. Bahá'í Faith
8. Confucianism
9. Jainism
10. Shintoism

Classically defined

Major religions have also been identified based on their importance, whether theological or temporal. The earliest Christian scholars, the first to define major religions, recognized only three religions: Christianity, Judaism, and Paganism (which they considered to encompass every other religion). Views evolved during the enlightenment, however, and, by the 19th century, Western scholars considered the five major religions to be Judaism, Christianity, Islam, Hinduism, and Buddhism. As the exposure of Westerners to other religions increased, five other religions were added to the original five: Confucianism, Taoism, Jainism, Shinto and Zoroastrianism. Later, the Bahá'í Faith was added to this list, resulting in eleven classic religions:

• Bahá'í Faith
• Buddhism
• Christianity
• Confucianism
• Hinduism
• Islam
• Jainism
• Judaism
• Shinto
• Taoism
• Zoroastrianism

The standard modern definition of major religion comes from the classical definition, often expanding on "Christianity," and omitting Jainism and Zoroastrianism, like this list found in the New York Public Library Student Reference:

• Bahá'í Faith
• Buddhism
• Confucianism
• Hinduism
• Islam
• Judaism
• Orthodox Eastern Church
• Protestantism
• Catholicism
• Shinto
• Taoism

References

• A discussion on definitions of major religions (http://www.adherents.com/Religions_By_Adherents.html)
• BBC Listing of Major Religions (http://www.bbc.co.uk/worldservice/people/features/world_religions/index.shtml)

See also: Religions of the world.