What is the most popular religion?

Answer 1

Christianity has 2.1 billion followers. Christianity is the most popular.

Islam has 1.87 billion followers and is the fastest growing religion.

Atheism is the third largest with about 1.1 billion followers.

Answer 2

Christianity of course.

Here's a list of Major Religions of the World Ranked by Number of Adherents:

note: Dnt expect it to be perfectly true as its approximate, hundreds of people are born n dying with each minute passing

Hope it helped

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
    
11. Spiritism: 15 million
    
12. Judaism: 14 million
    
13. Baha'i: 7 million
    
14. Jainism: 4.2 million
    
15. Shinto: 4 million
    
16. Cao Dai: 4 million
    
17. Zoroastrianism: 2.6 million
    
18. Tenrikyo: 2 million
    
19. Neo-Paganism: 1 million
    
20. Unitarian-Universalism: 800 thousand
    
21. Rastafarianism: 600 thousand
    
22. Scientology: 500 thousand