Numbers, Facts and Trends Shaping Your World

How the Global Religious Landscape Changed From 2010 to 2020

Muslims grew fastest; Christians lagged behind global population increase

How we did this

This report describes the world’s religious makeup in 2020 and how it changed from 2010. We focus on seven categories: Christians, Muslims, Hindus, Buddhists, Jews, people who belong to other religions, and those who are religiously unaffiliated.

The “other religions” category includes Baha’is, Daoists, Jains, Shintoists, Sikhs, Wiccans, Zoroastrians and many small groups, some of which can be described as folk or traditional religions. The religiously unaffiliated category – sometimes called “nones” – consists of people who do not identify with any religion.

This analysis is based on more than 2,700 sources of data, including national censuses, large-scale demographic surveys, general population surveys and population registers. The COVID-19 pandemic caused widespread delays in the collection of census and survey data, and some estimates for 2020 in this report are based on data that was not made public until 2024. At least 65 countries delayed their censuses, most of which originally were planned for 2020 or 2021.

Many censuses and surveys ask respondents a question like, “What is your religion, if any?” However, the exact wording of the question and the response options vary. We sorted a wide range of responses into the seven categories listed above. For example, the “Religiously unaffiliated” category includes people who say they are atheist, agnostic or “nothing in particular” in response to a Pew Research Center survey question about religious identity, as well as people who choose a “No religion” or “None” option in other surveys and national censuses.

To help explain the demographic dynamics that drove religious change between 2010 and 2020, we looked at religion-specific data on fertility rates and the age distribution of religious groups in each country, as well as mortality patterns for the overall population of each country.

In addition, we analyzed survey data about respondents’ childhood religions and their current religious identities (as adults) to estimate rates of religious “switching” – how many people have left or joined each religious group, including how many have left religion altogether.

Our estimates cover 201 countries and territories that had populations of at least 100,000 people in 2010 or 2020. Collectively, these places are home to 99.98% of the world’s population. Data on country population totals and general demographic characteristics come from the 2024 revision of the United Nations’ World Population Prospects.

This is the latest in an ongoing series of reports produced by Pew Research Center as part of the Pew-Templeton Global Religious Futures project, which analyzes religious change and its impact on societies around the world. Funding for the Global Religious Futures project comes from The Pew Charitable Trusts and the John Templeton Foundation (grant 62287). This publication does not necessarily reflect the views of the John Templeton Foundation.

Here is the full Methodology. Our interactive website allows you to explore the data in more detail.

The world’s population expanded from 2010 to 2020, and so did most religious groups, according to a Pew Research Center analysis of more than 2,700 censuses and surveys.

Christians remained the world’s biggest religious group. But Christians (of all denominations, counted as one group) did not keep pace with global population growth from 2010 to 2020.

Bar chart showing that Christians are the world’s largest religious group
  • The number of Christians rose by 122 million, reaching 2.3 billion.
  • Yet, as a share of the world’s population, Christians fell 1.8 percentage points, to 28.8%.

Muslims were the fastest-growing religious group over the decade.

  • The number of Muslims increased by 347 million – more than all other religions combined.
  • The share of the world’s population that is Muslim rose by 1.8 points, to 25.6%.
Bar chart showing Muslims were the fastest-growing religious group between 2010 and 2020

Buddhists were the only major religious group that had fewer people in 2020 than a decade earlier.

  • The number of Buddhists worldwide dropped by 19 million, declining to 324 million.
  • As a share of the global population, Buddhists slipped by 0.8 points, to 4.1%.

People with no religious affiliation – who are sometimes called “nones” were the only category aside from Muslims that grew as a percentage of the world’s population.1

Pie chart showing nearly a quarter of the world’s population is religiously unaffiliated
  • The number of religiously unaffiliated people rose by 270 million, reaching 1.9 billion.
  • The share of “nones” climbed nearly a full percentage point, to 24.2%.

Hindus grew at about the same rate as the world’s overall population.

  • The number of Hindus rose by 126 million, reaching 1.2 billion.
  • As a proportion of the global population, Hindus held steady at 14.9%.

Jews also held steady as a share of the world’s population.2

  • The number of Jews worldwide grew by nearly 1 million, reaching 14.8 million.
  • In percentage terms, Jews were the smallest group in the study, representing about 0.2% of the world’s population.

All other religions combined (including Baha’is, Daoists, Jains, Sikhs, adherents of folk religions and numerous other groups) expanded in tandem with the rest of the world. Their share of the global population held steady at 2.2%.

Collectively, 75.8% of the world’s people identified with a religion as of 2020. The remaining 24.2% did not identify with any religion, making people with no religious affiliation the third-largest group in this study, after Christians and Muslims.

Since 2010, the share of the global population that has any religious affiliation has declined by nearly 1 percentage point (from 76.7%) while the share without an affiliation has risen by the same amount (from 23.3%).

The growth of religious “nones” is striking because they are at a “demographic disadvantage” – their population is relatively old, on average, with relatively low fertility rates. However, unaffiliated people continued to grow as a share of the global population because many affiliated people around the world – primarily Christians – are “switching” out of religion.

How religious ‘nones’ grew despite their demographic disadvantage

Typically, change in population sizes is driven by demographic factors, including differences in groups’ fertility and mortality patterns, as well as their age distribution (also called “age structure”). Populations that are relatively young, on average, and have more children typically expand more quickly than those that are relatively old or have large numbers of people who die prematurely due to wars, diseases or famines.

When growth occurs because more babies are being born than people are dying, demographers call it “natural increase.” But the growth of the religiously unaffiliated population is not simply the result of natural increase. Indeed, at the global level, the “nones” population is older and has a lower fertility rate than Christians, Muslims and Hindus.3

The growth in the share of people around the world who are religiously unaffiliated is striking because low fertility and an older age structure put religiously unaffiliated people at what demographers call a disadvantage compared with the higher fertility and younger age of religiously affiliated people, globally.

So why did the world’s religiously unaffiliated population grow faster than the affiliated? Religious “switching” – especially people shedding their religious identity after having been raised as Christians – explains much of the unaffiliated population’s growth between 2010 and 2020.4

In other words, the large number of people leaving religion helped religiously unaffiliated people expand as a share of the global population, even though the growth of religiously unaffiliated people is slowed by demographic disadvantages such as being older and having fewer children, on average.

Regional change

Between 2010 and 2020, the share of the global population living in sub-Saharan Africa increased to 14.3% (up 2 percentage points), and the share living in the Middle East-North Africa region rose to 5.6% (up 0.5 points).

Line chart showing sub-Saharan Africa has surpassed Europe to become the region where the most Christians live

Every other region held a smaller share of the world’s population in 2020 than in 2010. These shifts are reflected in the geographic distribution of some religious groups, including Christians.

Sub-Saharan Africa is now home to the largest number of Christians, surpassing Europe. As of 2020, 30.7% of the world’s Christians live in sub-Saharan Africa, compared with 22.3% in Europe. This change was fueled by differences in the two regions’ rates of natural increase (with much higher fertility rates in Africa than in Europe), as well as by widespread Christian disaffiliation in Western Europe.

The regional concentration of Jews also has changed. As of 2020, 45.9% of Jews live in the Middle East-North Africa region, while 41.2% reside in North America. In 2010, North America was the region where the largest number of Jews lived. This shift was primarily the result of Israel’s Jewish population growing from 5.8 million to 6.8 million between 2010 and 2020, through a combination of natural increase and migration.5

Changes within countries

Another way to assess religious change is to look at how many countries and territories experienced a substantial shift in their religious makeup. In this section, we focus on places where a religious group’s share of the overall population grew or shrank by at least 5 percentage points between 2010 and 2020. (For a discussion of the challenge of measuring the statistical significance of changes in religious composition, refer to the Methodology.)

Chart showing religiously unaffiliated populations grew substantially in 35 countries

Christians experienced a substantial change, as defined above, in more countries (41) than any other religious group. In all but one case, Christians shrank as a share of the population. Most of the countries experiencing declines were in the Americas and Europe. The decreases ranged from a 5-point drop in Benin to a 14-point drop in the U.S. and a 20-point drop in Australia.

Only in Mozambique did the share of the population that is Christian grow substantially between 2010 and 2020, rising by 5 percentage points.

Few countries experienced substantial changes in the percentage of Muslims in their populations. Although the global Muslim population grew at a faster rate than any other major religion between 2010 and 2020, this was largely because of overall population growth in the countries where Muslims are concentrated. Muslim shares are estimated to have risen by at least 5 points in Kazakhstan, Benin and Lebanon, and to have dropped by at least 5 points in Tanzania and Oman.

In addition, there were declines of 7 points in the Buddhist share of South Korea’s population and in the share that people of other religions made up of Guinea-Bissau’s population.

Religiously unaffiliated people experienced the largest number of substantial increases. People of no religion gained at least 5 percentage points in 35 countries spread across the globe. The unaffiliated grew the most (as a share of each country’s total population) in the U.S. (up 13 points), Uruguay (up 16 points), Chile (up 17 points) and Australia (up 17 points).

The United States, as of 2020, is the country with the world’s second-largest number of religiously unaffiliated people (after China), surpassing Japan.

Chart showing China has 7 times as many religiously unaffiliated people as the U.S. and Japan combined

The U.S. had roughly 101 million religious “nones” in 2020 (up 97% from a decade earlier), while Japan had 73 million (up 8%). However, the unaffiliated category continues to account for a much larger share of the total population in Japan – 57% of all Japanese are religiously unaffiliated – than in the U.S., where 30% identify as atheist, agnostic or “nothing in particular.”

In both 2010 and 2020, China had more religiously unaffiliated people than any other country. China’s 1.3 billion unaffiliated people made up 90% of its total population in 2020.6

Most countries still have Christian majorities

Due to disaffiliation from Christianity, there now are fewer Christian-majority countries and more countries with a religiously unaffiliated majority than there were in 2010.

Table showing Christians were a majority in 59.7% of all places analyzed

As of 2020, Christians were a majority in 120 countries and territories, down from 124 a decade earlier. Christians dropped below 50% of the population in the United Kingdom (49%), Australia (47%), France (46%) and Uruguay (44%). In each of these places, religiously unaffiliated people now account for 40% or more of the population, and smaller religious groups such as Muslims, Hindus, Buddhists, Jews or adherents of other religions (combined) account for 11% or less.

Over the same period, religiously unaffiliated people became a majority in the Netherlands (54%), Uruguay (52%) and New Zealand (51%), raising the number of places with an unaffiliated majority from seven to 10. (These countries joined China, North Korea, the Czech Republic, Hong Kong, Vietnam, Macao and Japan, which already had religiously unaffiliated majorities in 2010.)

Table showing the Netherlands, New Zealand and Uruguay now have religiously unaffiliated majorities

There was no change in the number of places in which the majority of the population are Muslim (53), Buddhist (7), Jewish (1) or followers of other religions (1).7

These are among the key findings of a Pew Research Center of more than 2,700 censuses and surveys, including census data releases that were delayed due to the coronavirus pandemic. The study is part of the Pew-Templeton Global Religious Futures project, which seeks to understand global religious change and its impact on societies.

The rest of this Overview discusses: Why religious change occurred at the global level between 2010 and 2020; the connection between economic development and religious affiliation; religious groups’ geographic distributions and age profiles in 2020; and whether religious groups live as religious majorities or minorities within countries.

It concludes with an explanation of how and why we have revised our 2010 estimates and updated our methods for making demographic estimates.

Why change occurred at the global level

Global change in the size of religious populations is the result of two primary mechanisms: religious “switching” and natural increase (i.e., the difference between births and deaths). The latter is influenced by several demographic factors: age structure, fertility and mortality (or life expectancy).

How much change each mechanism creates varies by religion:

  • Religious disaffiliation is the main driver of the decline in the Christian share of the global population.
  • Religious disaffiliation – primarily of people leaving Christianity – also is the main driver of the growth of religiously unaffiliated populations.
  • Increases in the global Muslim population are largely due to Muslims having a relatively young age structure and high fertility rate, two characteristics that result in natural population growth.

In addition, migration is a source of religious change within some regions and countries. But migration does not affect religious group sizes at the global level (as long as people remain bound to this planet). For more about the regional and country-level impact of migration, read Chapter 1.

Religious ‘switching’

Although most people around the world still identify with the religion in which they were raised, religious switching is pervasive. Overall, there’s been a net movement of people switching into the religiously unaffiliated category.

This Pew Research Center study is the first to report on observed patterns of switching into and out of religious groups at the global level.8 In many countries, this change has followed a generational pattern: Each new generation of young adults has contained a larger share of people who are religiously unaffiliated, either because they were not raised in any religion or because they have switched away from the religion in which they were raised.

What is religious ‘switching’?

Throughout this report, religious switching refers to a change between the religious group in which a person says they were raised (during their childhood) and their religious identity now (in adulthood).

We use the term “switching” rather than “conversion” because many people who switch identities leave religion to become religiously unaffiliated.

We count changes between seven large religious categories (such as from Buddhist to Christian, or from Hindu to religiously unaffiliated) but not switching within each category (such as from Catholic to Protestant).

Many more people grew up with a religion than grew up with no religion. And most people, as adults, still identify with a religion. But the balance between the groups is changing.

Chart showing that worldwide, 3 adults have left a religion for every adult who has joined

Using surveys from 117 countries and territories, we analyzed data from adult respondents and compared the religion they say they were raised in (as children) with their current religious identity (as adults).9

To capture switching that has occurred in more recent years, we use data from adults ages 18 to 54. Religious switching is more common earlier in life, though it can happen at any age.

We found that for every adult in that age group who says they joined a religion after having been raised without a religion, 3.2 moved in the other direction – they left religion altogether after having been raised in one.

As a result, based on this set of measures, the religiously unaffiliated category has had the largest net gain due to switching.

Christians have experienced the biggest net losses from switching (3.1 have left for every 1.0 who has joined). Most former Christians no longer identify with any religion, but some now identify with a different religion.

Buddhists also have had more people leave than join (1.8 left, 1.0 joined).

Hindus have had more people leave than join, while the reverse is true for Muslims. However, religious switching into or out of these two groups is relatively uncommon, so the modest differences in the ratio of leavers to joiners has a small overall effect on the size of Hindu and Muslim populations.

For more details about religious switching, read Chapter 1.10

Religious ‘switching’ out of Christianity in the United States

The share of the U.S. population – including children – who are Christian dropped from 78.3% in 2010 to 64.0% in 2020, while the share who are religiously unaffiliated rose from 16.5% to 29.7%, according to our analysis. (These estimates for people of all ages differ slightly from the figures for U.S. adults ages 18 and older that Pew Research Center published in the 2023-24 U.S. Religious Landscape Study, or RLS.)

The United States is one of many countries where large numbers of Christians have become religiously unaffiliated. Moreover, younger generations in the U.S. are less likely than older generations to identify as Christian.

If these switching patterns and generational differences persist, then in the long term, the share of Christians in the U.S. population will continue to fall and the share of unaffiliated people will continue to rise. However, our surveys since 2020 indicate that the percentage of Americans who identify as Christians may have leveled off, at least temporarily. Read more in the 2023-24 RLS.

Natural increase

Natural population growth – the extent to which births outnumber deaths – is greater for religious groups that have higher fertility rates and lower mortality rates.

In a report published in 2017, we modeled the number of births and deaths that occurred globally between 2010 and 2015. We estimated that Muslims gained the most via natural increase, followed by Christians. By contrast, natural growth among the religiously unaffiliated was modest.

Groups’ varied rates of natural increase are partly the result of geographic distribution. Religions that are concentrated in parts of the globe with relatively high overall population growth (such as the Middle East-North Africa region and sub-Saharan Africa) naturally would expand more quickly than those concentrated in low-growth regions (such as North America, the Asia-Pacific region and Europe).

Muslims and Christians have a large presence in the rapidly growing region of sub-Saharan Africa, but many Christians also live in the slower-growth regions of Europe and the Americas. Religiously unaffiliated people and Buddhists are heavily concentrated in countries that have shrunk as a share of the world’s population, including China and Japan.

Nevertheless, religious differences sometimes appear to play a role in fertility, even after accounting for geography. For example, Nigerian Muslims have a higher average birth rate than Nigerian Christians, and Hindus in India have a higher fertility rate than Buddhists in India. These differences also may be related to other factors, such as education, access to birth control and women’s workforce participation rates.

For more details about natural growth patterns, read Chapter 1.

Economic development and religious affiliation

People in wealthier parts of the world are, on average, less religious than those in societies with less advanced economies. This pattern holds true across many different measures of religion – such as rates of daily prayer and belief in god – and across many indicators of economic development. For example, Pew Research Center in 2018 found that people in countries with higher life expectancy at birth are less likely to attend religious services weekly.11

To get a more general sense of this pattern, it helps to look at country scores on the United Nations’ Human Development Index (HDI), which combines data on life expectancy, education and income.

We find that countries with high HDI scores (i.e., those that are more developed) tend to have lower rates of religious affiliation. In many of these countries, Christianity is the most common religion. In a few Asian countries with high HDI scores and low affiliation rates, Buddhism is the largest religion. In some countries, the religiously unaffiliated category is approaching or already exceeds the largest religious group in size.

Countries with low HDI scores, on the other hand, tend to have high rates of religious affiliation.

Economic development is not perfectly correlated with religion, and there are some countries with high rates of religious affiliation across the range of HDI scores. This includes many Muslim-majority countries, Hindu-majority India and Nepal, and Jewish-majority Israel.

Chart showing economically advanced countries tend to have smaller shares of religiously affiliated people

Geographic distribution of religious groups in 2020

Nearly six-in-ten people worldwide live in the Asia-Pacific region, including most people in five religious categories: 99% of Hindus, 98% of Buddhists, 78% of the religiously unaffiliated, 65% of followers of other religions, and 59% of Muslims.

Christians are the most geographically dispersed group. The largest share of Christians live in sub-Saharan Africa (31%), followed by the Latin America-Caribbean region (24%) and Europe (22%). This is a major geographic change since the early 1900s, when Christians in sub-Saharan Africa made up 1% of the global Christian population and two-thirds of Christians lived in Europe.

Most Jews live either in the Middle East-North Africa region or in North America.

Bar chart showing Christians are the world’s most evenly distributed religious group

Age profile of religious groups in 2020

As of 2020, Muslims have the highest proportion of children in their population (33% of all Muslims worldwide are under 15). Jews and Buddhists have the highest proportion of older adults; 36% in each group are ages 50 and older.

Much of the variation in the age structure of religious groups is driven by their geographic concentration. For example, about half of the world’s Jews live in North America and Europe, regions that have relatively old populations.

The youthfulness of Muslims is tied to the fact that nearly four-in-ten of the world’s Muslims live in sub-Saharan Africa and the Middle East-North Africa region – places with relatively young populations.

Bar chart showing the vast majority of Muslims around the world are younger than 50

Christians have a large presence in many regions, from the most youthful (sub-Saharan Africa) to the least (Europe). Among religious groups, Christians have the median age (30.8 years) closest to the world’s overall median age (30.6).

If religious groups are heavily clustered in just one country, their global age structure reflects that country’s characteristics. For instance, the global age distribution of Hindus mirrors the age distribution of India, which is home to 95% of the world’s Hindus. Similarly, the age profile of religiously unaffiliated people resembles that of China, which is home to 67% of all unaffiliated people.

Table showing Buddhists are older than other religious groups, with a median age of 39.8 years

Do people mostly live as religious majorities or minorities?

Around the world, 80% of all people live in a place in which most other people share their religious identity. People living as a religious minority in their country make up 20% of the world’s population.

This analysis does not divide the seven major religious categories into subgroups, so Protestants living in Catholic-majority countries or Shiite Muslims living in Sunni-majority countries, for example, are considered to be living in a place where their broader faith is in the majority.

Bar chart showing 84% of Christians live in places where Christianity is the majority religion

Hindus are most likely to live as a religious majority, with 97% living in the world’s two Hindu-majority countries, India and Nepal. About eight-in-ten Muslims are part of a religious majority, as are similar shares of Christians and religiously unaffiliated people. Slightly fewer than half of all Buddhists and Jews live as a majority.

The world’s seven Buddhist-majority countries (Cambodia; Thailand; Myanmar, also known as Burma; Bhutan; Sri Lanka; Laos; and Mongolia) are home to 47% of all Buddhists. Israel, the sole Jewish-majority country, is home to 46% of all Jews. Taiwan is the only place where members of other religions are in the majority, and 7% of all people in the “other religion” category, worldwide, live in Taiwan. (Many Taiwanese people practice Daoism and traditional folk religions. Read more about Taiwan’s religious beliefs and practices in our report “Religion and Spirituality in East Asian Societies.”)

Revising previous estimates

The 2010 estimates in this report differ from what we have published in the past. We adjusted our data sources and methods to make our estimates for 2010 and 2020 as reliable and comparable as possible.

Most consequentially, we changed how we measure China’s religious composition. In the past, we used custom estimates for China to adjust for the fact that surveys in China often do not fully capture people’s religious identity. This report relies on measures of zongjiao religious identity, as these are the most comparable with what we use in every other country, as well as the most readily comparable over time in China. (The measure of formal zongjiao religious identity commonly used in Chinese surveys excludes people who engage in religious or spiritual beliefs and practices but do not consider themselves affiliated with any religion.)

According to our new approach, 10% of China’s population identified with a religion in 2020, the lowest share of any country in the study. Since China has such a large population, this new approach has increased our estimate of the religiously unaffiliated share of the world’s population.

Read more about the challenges of measuring religion in China in our 2023 report. More information about improvements in our methodology is available in Chapter 15 and in the Methodology.

Recommended Citation:

Conrad Hackett, Marcin Stonawski, Yunping Tong, Stephanie Kramer, Anne Fengyan Shi, and Dalia Fahmy. 2025. “How the Global Religious Landscape Changed From 2010 to 2020.” Pew Research Center doi: 10.58094/fj71-ny11

  1. The “Religiously unaffiliated” category includes people who say they are atheist, agnostic or “nothing in particular” in response to a Pew Research Center survey question about religious identity, as well as people who choose a “No religion” or “None” option in other surveys and national censuses. While they do not identify with any religion, some religiously unaffiliated people do hold religious or spiritual beliefs and engage in religious or spiritual practices – though typically at lower levels than are found among people in the same country who have a religious affiliation. For details, read our 2024 report “Religious ‘Nones‘ in America: Who They Are and What They Believe” and our 2018 report “Being Christian in Western Europe.”
  2. Outside of Israel, we generally use a definition of Jewishness based on self-identification with Judaism as a religion. Our estimate for Israel is based on the government’s population register of Jews in Israel, which only counts people as Jewish if they meet halakhic (religious) legal criteria – i.e., children of Jewish mothers as well as people who have undergone conversions recognized by the government.
  3. At the global level, religiously unaffiliated people are older than affiliated people, on average. However, at the country level, the opposite pattern is often true. The unaffiliated are younger than the affiliated in China, Japan and most countries in Europe and the Americas, including the United States. This pattern reversal is an example of a mathematical phenomenon called Simpson’s paradox. Because China and Japan have such large populations, their age patterns have a big influence on global averages. Both countries have unaffiliated majorities and high median ages.
  4. Terms such as “conversion,” “reversion” and “apostasy” also are sometimes used to describe the choice to enter or leave a religious group. We use the term “switching” because the movement can take place in all directions, including leaving religion entirely, and does not necessarily involve any formal ritual.
  5. The size of the Jewish populations in Israel and North America depends on the definition of Jewishness. For more information, jump to Chapter 8.
  6. The population of religiously unaffiliated people in China (as in other countries) includes some people who engage in activities and hold beliefs that can be considered religious or spiritual, even though they don’t describe themselves as belonging to any religion. For more about the unaffiliated in China, refer to our report “Measuring Religion in China.”
  7. Taiwan is the only place in which the “other religions” category constitutes a majority. This reflects large numbers of Daoists and practitioners of Chinese folk religions in Taiwan.
  8. This report is the first to provide global estimates of religious switching. Several previous Pew Research Center reports have described country-level patterns of religious switching. For example, “Around the World, Many People Are Leaving Their Childhood Religions” reports on switching patterns in 36 countries.
  9. We weighted data by each place’s population size in 2010 so that countries and territories with larger populations of each group have more influence on the global results for that group. These 117 surveys are from places that were home to 92% of the world’s 18- to 54-year-olds in 2010. For more details, read the Methodology.
  10. Chapter 1 discusses the challenges of measuring religious switching among Jews and among the “other religions” category.
  11. A popular theory is that rising economic and existential security leads to religious decline. Studies have tested and developed this theory in many contexts. For an overview of this literature, read Molteni, Francesco. 2024. “Rising Security and Religious Decline: Refining and Extending Insecurity Theory.” Sociology of Religion.
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