List of religious populations

Which religion is the largest? Which religion is the smallest? Our planet’s population of about 8 billion people follows myriad religions in widely varying numbers. The following tables draw from information available at the World Religion Database at Boston University and is based on data for the world’s population as of 2020 (7.8 billion humans). The populations of each religion are listed from highest to lowest.

The first table does not divide the most populous religions into specific sects. The second table reorganizes the data and order by replacing some of the largest religions with their internal subdivisions. The list breaks up broad categories such as Christianity and Islam and lists separately more specific traditions such as Roman Catholicism or Sunni Islam. The second chart thereby shows a slightly different picture of the world’s religious diversity and relative populations.

Populations of world religions in 2020

Populations of world religions in 2020 with sects

Source: Gina A. Zurlo, World Religion Database (Leiden/Boston: Brill, accessed June 2024). (Subscription required to access.)

Discover how ordinary objects work, and expand your understanding of the familiar.

SIGN UP

" height="20" alt="HEW Logo">

Thank you for signing up!"

Back to homepage

By clicking "Sign Up", you consent to the Britannica Privacy Policy and Terms of Use.

Overview

Many possible readings and interpretations can flow from this data, and readers are invited to make of this information what they wish. These religious population numbers are interesting for academic or research purposes, and they might also provide adherents a sense of collective identity—there are x number of “us.” It is also worth noting that larger populations do not indicate a stronger claim to religious truth, nor does a small population indicate a wrong religion. Religion is not a popularity contest. Per the second chart, agnosticism—which the World Religion Database defines as no religion or the inability to know the existence of deities—is the third largest religious identity in 2020. Rather, a view of the world’s religious makeup provides a sense of the world’s current religious variety and allows potential insights into how religious populations impact, and are impacted by, many aspects of human affairs from beliefs to politics to history.

As religions spring up, spread, and fade away, and as their followers are born, die, or convert, the world’s religious makeup is constantly changing. Note that one of the world’s oldest religions, Zoroastrianism, is also by far the smallest, while the “New Religionists”—followers of a variety of new religious movements founded in the 20th century in Asia—are quite numerous. Many religions that were historically influential—e.g., Greek, Roman, Egyptian, and Mesopotamian religions—are notably absent. A snapshot of the river of religion, as provided in these lists, shows only a momentary splash of water out of that great river’s roaring flow from ancient times to the present across the wide world of humanity.