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This information is reproduced from www.adherents.com/Religions_By_Adherents.html and this web site has much more detailed information available.

(Sizes shown are approximate estimates, and are here mainly for the purpose of ordering the groups, not providing a definitive number. This list is sociological/statistical in perspective.)

  1. Christianity (2 billion)
  2. Islam (1.3 billion)
  3. Hinduism (900 million)
  4. Secular/Nonreligious/Agnostic/Atheist (850 million)
  5. Buddhism (360 million)
  6. Chinese traditional religion (225 million)
  7. primal-indigenous (150 million)
  8. African Traditional & Diasporic (95 million)
  9. Sikhism (23 million)
  10. Juche (19 million)
  11. Spiritism (14 million)
  12. Judaism (14 million)
  13. Baha'i (6 million)
  14. Jainism (4 million)
  15. Shinto (4 million)
  16. Cao Dai (3 million)
  17. Tenrikyo (2.4 million)
  18. Neo-Paganism (1 million)
  19. Unitarian-Universalism (800 thousand)
  20. Rastafarianism (700 thousand)
  21. Scientology (600 thousand)
  22. Zoroastrianism (150 thousand)

The adherent counts presented in the list above are estimates of the number of people who have at least a minimal level of self-identification as adherents of the religion. Levels of participation vary within all groups. These numbers tend toward the high end of reasonable worldwide estimates. Valid arguments can be made for different figures, but if the same criteria are used for all groups, the relative order should be the same.

This listing is not a comprehensive list of all religions, only the "major" ones (as defined below). There are distinct religions other than the ones listed above. But this list accounts for the religions of over 98% of the world's population.

Christianity | Anglican | Catholic | Evangelical | Jehovah's Witnesses | Latter-day Saints | Orthodox | Pentecostal
Islam | Hinduism | Buddhism | Sikhism | Judaism | more links