Ranked by Number of Adherents

Introduction
The adherent counts presented in the list above are current 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. Further details and sources are available below and in the Adherents.com main database.
1. Christianity: 2.1 billion
2. Islam: 1.5 billion
3. Secular/Nonreligious/Agnostic/Atheist: 1.1 billion
4. Hinduism: 900 million
5. Chinese traditional religion: 394 million
6. Buddhism: 376 million
7. primal-indigenous: 300 million
8. African Traditional & Diasporic: 100 million
9. Sikhism: 23 million
10. Juche: 19 million
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