In 2022, around 31.6 percent of the global population were identify as Christian. Around 25.8 percent of the global population identify as Muslims, followed by 15.1 percent of global populations as Hindu.

As of 2010, Christianity was the religion with the most followers worldwide, followed by Islam (Muslims) and Hinduism. In the forty years between 2010 and 2050, it is projected that the landscape of world religions will undergo some noticeable changes, with the number of Muslims almost catching up to Christians. The changes in population sizes of each religious group is largely dependent on demographic development, for example, the rise in the world's Christian population will largely be driven by population growth in Sub-Saharan Africa, while Muslim populations will rise across various regions of Africa and South Asia. As India's population is set to grow while China's goes into decline, this will be reflected in the fact that Hindus will outnumber the unaffiliated by 2050. In fact, India may be home to both the largest Hindu and Muslim populations in the world by the middle of this century.

Christianity was the largest religion in a high number of the countries included in the survey. Of the countries, Peru, South Africa, and Poland had the highest share of Christians at around 75 percent. Moreover, around 90 percent in India and Thailand stated that they believed in another religion, with Hinduism and Buddhism being the major religion in the two countries respectively. Sweden and South Korea were the only two countries where 50 percent or more of the respondents stated that they did not have any religious beliefs.

The World Religion Project (WRP) aims to provide detailed information about religious adherence worldwide since 1945. It contains data about the number of adherents by religion in each of the states in the international system. These numbers are given for every half-decade period (1945, 1950, etc., through 2010). Percentages of the states' populations that practice a given religion are also provided. (Note: These percentages are expressed as decimals, ranging from 0 to 1, where 0 indicates that 0 percent of the population practices a given religion and 1 indicates that 100 percent of the population practices that religion.) Some of the religions are divided into religious families. To the extent data are available, the breakdown of adherents within a given religion into religious families is also provided.

The project was developed in three stages. The first stage consisted of the formation of a religion tree. A religion tree is a systematic classification of major religions and of religious families within those major religions. To develop the religion tree we prepared a comprehensive literature review, the aim of which was (i) to define a religion, (ii) to find tangible indicators of a given religion of religious families within a major religion, and (iii) to identify existing efforts at classifying world religions. (Please see the original survey instrument to view the structure of the religion tree.) The second stage consisted of the identification of major data sources of religious adherence and the collection of data from these sources according to the religion tree classification. This created a dataset that included multiple records for some states for a given point in time. It also contained multiple missing data for specific states, specific time periods and specific religions. The third stage consisted of cleaning the data, reconciling discrepancies of information from different sources and imputing data for the missing cases.

The National Religion Dataset: The observation in this dataset is a state-five-year unit. This dataset provides information regarding the number of adherents by religions, as well as the percentage of the state's population practicing a given religion.

From 2022 to 2060, the worldwide population of Muslims is expected to increase by 45.7 percent. For the same period, the global population of Buddhists is expected to decrease by 12.2 percent.

In 2022, 99 percent of Hindus and Buddhists worldwide lived in Asia-Pacific. In comparison, 43 percent of Jews lived in North America, and 45.4 percent lived in the Middle East and North Africa. Christians were more evenly divided around the continents.

Census: Population: by Religion: Christian: Punjab data was reported at 348,230.000 Person in 03-01-2011. This records an increase from the previous number of 292,800.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Punjab data is updated decadal, averaging 320,515.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 348,230.000 Person in 03-01-2011 and a record low of 292,800.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Punjab data remains active status in CEIC and is reported by Office of the Registrar General & Census Commissioner, India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE004: Census: Population: by Religion: Christian.

Census: Population: by Religion: Christian: Kerala data was reported at 2,385,605.000 Person in 03-01-2011. This records an increase from the previous number of 1,426,646.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Kerala data is updated decadal, averaging 1,906,125.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 2,385,605.000 Person in 03-01-2011 and a record low of 1,426,646.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Kerala data remains active status in CEIC and is reported by Office of the Registrar General & Census Commissioner, India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE004: Census: Population: by Religion: Christian.

This study, designed and carried out by the "http://www.asarb.org/" Target="_blank">Association of Statisticians of American Religious Bodies (ASARB), compiled data on 372 religious bodies by county in the United States. Of these, the ASARB was able to gather data on congregations and adherents for 217 religious bodies and on congregations only for 155. Participating bodies included 354 Christian denominations, associations, or communions (including Latter-day Saints, Messianic Jews, and Unitarian/Universalist groups); counts of Jain, Shinto, Sikh, Tao, Zoroastrian, American Ethical Union, and National Spiritualist Association congregations, and counts of congregations and adherents from Baha'i, three Buddhist groupings, two Hindu groupings, four Jewish groupings, and Muslims. The 372 groups reported a total of 356,642 congregations with 161,224,088 adherents, comprising 48.6 percent of the total U.S. population of 331,449,281. Membership totals were estimated for some religious groups.

In January 2024, the ARDA added 21 religious tradition (RELTRAD) variables to this dataset. These variables start at variable #12 (TOTCNG_2020). Categories were assigned based on pages 88-94 in the original "https://www.usreligioncensus.org/index.php/node/1638" Target="_blank">2020 U.S. Religion Census Report.

Visit the "https://www.thearda.com/us-religion/sources-for-religious-congregations-membership-data" Target="_blank">frequently asked questions page for more information about the ARDA's religious congregation and membership data sources.

Census: Population: by Religion: Christian: Delhi data was reported at 146,093.000 Person in 03-01-2011. This records an increase from the previous number of 130,319.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Delhi data is updated decadal, averaging 138,206.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 146,093.000 Person in 03-01-2011 and a record low of 130,319.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Delhi data remains active status in CEIC and is reported by Office of the Registrar General & Census Commissioner, India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE004: Census: Population: by Religion: Christian.

India Census: Population: by Religion: Muslim: Urban data was reported at 68,740,419.000 Person in 2011. This records an increase from the previous number of 49,393,496.000 Person for 2001. India Census: Population: by Religion: Muslim: Urban data is updated yearly, averaging 59,066,957.500 Person from Mar 2001 (Median) to 2011, with 2 observations. The data reached an all-time high of 68,740,419.000 Person in 2011 and a record low of 49,393,496.000 Person in 2001. India Census: Population: by Religion: Muslim: Urban data remains active status in CEIC and is reported by Census of India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE001: Census: Population: by Religion.

This statistic shows the top 25 countries in the world with the largest number of Christian population in 2010. In 2010, the United States was leading the ranking with about 243 million Christians living in the country.

This study assessed the effects of male inmate religiosity on post-release community adjustment and investigated the circumstances under which these effects were most likely to take place. The researcher carried out this study by adding Federal Bureau of Investigation criminal history information to an existing database (Clear et al.) that studied the relationship between an inmate's religiousness and his adjustment to the correctional setting. Four types of information were used in this study. The first three types were obtained by the original research team and included an inmate values and religiousness instrument, a pre-release questionnaire, and a three-month post-release follow-up phone survey. The fourth type of information, official criminal history reports, was later added to the original dataset by the principal investigator for this study. The prisoner values survey collected information on what the respondent would do if a friend sold drugs from the cell or if inmates of his race attacked others. Respondents were also asked if they thought God was revealed in the scriptures, if they shared their faith with others, and if they took active part in religious services. Information collected from the pre-release questionnaire included whether the respondent attended group therapy, religious groups with whom he would live, types of treatment programs he would participate in after prison, employment plans, how often he would go to church, whether he would be angry more in prison or in the free world, and whether he would be more afraid of being attacked in prison or in the free world. Each inmate also described his criminal history and indicated whether he thought he was able to do things as well as most others, whether he was satisfied with himself on the whole or felt that he was a failure, whether religion was talked about in the home, how often he attended religious services, whether he had friends who were religious while growing up, whether he had friends who were religious while in prison, and how often he participated in religious inmate counseling, religious services, in-prison religious seminars, and community service projects. The three-month post-release follow-up phone survey collected information on whether the respondent was involved with a church group, if the respondent was working for pay, if the respondent and his household received public assistance, if he attended religious services since his release, with whom the respondent was living, and types of treatment programs attended. Official post-release criminal records include information on the offenses the respondent was arrested and incarcerated for, prior arrests and incarcerations, rearrests, outcomes of offenses of rearrests, follow-up period to first rearrest, prison adjustment indicator, self-esteem indicator, time served, and measurements of the respondent's level of religious belief and personal identity. Demographic variables include respondent's faith, race, marital status, education, age at first arrest and incarceration, and age at incarceration for rearrest.

Opinion on religion and politics or religion and church as well as society.

1. Party proximity: intention to vote in the next Bundestag election and party preference (Sunday question); alternatively electable parties; vote decision in the last Bundestag election; sympathy scale for the parties CDU/CSU, SPD, FDP, Linke, Grüne, NPD, Republicans and DVU.

2. Religion and politics: opinion on more religious people in public office; opinion on the influence of church leaders on government decisions; opinion on the weight of churches in the CDU; significance of Christianity in the CDU or CSU in a possible vote decision for these parties.

3. Religion and church: attitudes to religion and church (more peaceful world without religion, religion yes, church no, with church and religion nothing in mind); only one true religion, important truths in many religions or in no religion; opinion on Islamic education for Muslim children in state schools in Germany; denomination; frequency of churchgoing; church affiliation; former denomination or religious community or possible membership of a religious community (only those without denomination); self-assessment of religiousness; religiousness of the parental home; future significance of religion; attitude to a church burial.

4. Beliefs: faith in God or in a spiritual power; drawing comfort and strength from faith; faith in a life after death; faith in the devil; faith in a rebirth; optimism about the future.

5. Social acceptance: attitude to homosexuality, single parent education, abortion and euthanasia on demand.

6. Societal development: concerns regarding: loss of traditional values, more and more people on the losing side, destruction of livelihoods through pollution; opinion on control of life through secret agreements and plans; natural calling of women to create a climate of security for the family; loss of social ideals.

Demography: sex; age; marital status; cohabitation with a partner; children; number of children; education: school-leaving certificate or desired school-leaving certificate; university degree; completed apprenticeship; employment status; job security; current or former occupational status; household size; number of persons in the household aged 18 and over; trade union member in the household; party affiliation; strength of party affiliation; type of party affiliation; basic party affiliation or current party affiliation; number of telephone numbers in the household.

Additionally coded was: questionnaire no.; federal state where the respondent is entitled to vote; residential district formerly West Berlin or East Berlin; city size; weighting factor.

Philippines Population: RA: Tribal Religions data was reported at 243,704.000 Person in 2015. This records an increase from the previous number of 207,246.000 Person for 2010. Philippines Population: RA: Tribal Religions data is updated yearly, averaging 207,246.000 Person from Dec 2000 (Median) to 2015, with 3 observations. The data reached an all-time high of 243,704.000 Person in 2015 and a record low of 164,080.000 Person in 2000. Philippines Population: RA: Tribal Religions data remains active status in CEIC and is reported by Philippine Statistics Authority. The data is categorized under Global Database’s Philippines – Table PH.G003: Population: Religious: Affiliation.

Singapore Population: Religion: Islam data was reported at 459.800 Person th in 2015. This records an increase from the previous number of 457.435 Person th for 2010. Singapore Population: Religion: Islam data is updated yearly, averaging 457.435 Person th from Jun 2000 (Median) to 2015, with 3 observations. The data reached an all-time high of 459.800 Person th in 2015 and a record low of 371.660 Person th in 2000. Singapore Population: Religion: Islam data remains active status in CEIC and is reported by Department of Statistics. The data is categorized under Global Database’s Singapore – Table SG.G002: Population by Religion .

Census: Population: by Religion: Muslim: Bihar: Male data was reported at 9,044,086.000 Person in 03-01-2011. This records an increase from the previous number of 7,061,908.000 Person for 03-01-2001. Census: Population: by Religion: Muslim: Bihar: Male data is updated decadal, averaging 8,052,997.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 9,044,086.000 Person in 03-01-2011 and a record low of 7,061,908.000 Person in 03-01-2001. Census: Population: by Religion: Muslim: Bihar: Male data remains active status in CEIC and is reported by Office of the Registrar General & Census Commissioner, India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE003: Census: Population: by Religion: Muslim.

In 2023, over 87 percent of Indonesians declared themselves to be Muslim, followed by 7.4 percent who were Christians. Indonesia has the largest Islamic population in the world and for this reason is often recognized as a Muslim nation. However, Indonesia is not a Muslim nation according to its constitution. The archipelago is a multifaith country and officially recognizes six religions – Islam, Protestantism, Catholicism, Buddhism, Hinduism, and Confucianism.

Not all provinces in Indonesia are Muslim majority
The spread of Islam in Indonesia began on the west side of the archipelago, where the main maritime trade routes were located. Until today, most of the Indonesian Muslim population are residing in Western and Central Indonesia, while the majority religion of several provinces in Eastern Indonesia, such as East Nusa Tenggara and Bali, is Christian and Hindu, respectively.

Discrimination towards other beliefs in Indonesia The Indonesian constitution provides for freedom of religion. However, the Government Restrictions Index Score on religion in Indonesia is relatively high. Indonesians who practice unrecognized religions, including Indonesia’s indigenous or traditional belief systems, such as animism, dynamism, and totemism, face legal restrictions and discrimination. Indonesian law requires its citizens to put one of the recognized religions on their national identity cards, with some exceptions for indigenous religions. Although legally citizens may leave the section blank, atheism or agnosticism is considered uncommon in Indonesia.

Census: Population: by Religion: Muslim: Daman and Diu data was reported at 19,277.000 Person in 03-01-2011. This records an increase from the previous number of 12,281.000 Person for 03-01-2001. Census: Population: by Religion: Muslim: Daman and Diu data is updated decadal, averaging 15,779.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 19,277.000 Person in 03-01-2011 and a record low of 12,281.000 Person in 03-01-2001. Census: Population: by Religion: Muslim: Daman and Diu data remains active status in CEIC and is reported by Office of the Registrar General & Census Commissioner, India. The data is categorized under India Premium Database’s Demographic – Table IN.GAE003: Census: Population: by Religion: Muslim.

Singapore Population: Religion: Female: Islam data was reported at 233.800 Person th in 2015. This records an increase from the previous number of 231.478 Person th for 2010. Singapore Population: Religion: Female: Islam data is updated yearly, averaging 231.478 Person th from Jun 2000 (Median) to 2015, with 3 observations. The data reached an all-time high of 233.800 Person th in 2015 and a record low of 185.804 Person th in 2000. Singapore Population: Religion: Female: Islam data remains active status in CEIC and is reported by Department of Statistics. The data is categorized under Global Database’s Singapore – Table SG.G002: Population by Religion .