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.

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 (as detailed below) 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 Global Religion Dataset: This dataset uses a religion-by-five-year unit. It aggregates the number of adherents of a given religion and religious group globally by five-year periods.

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.

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.

As of 2020, Christianity was the largest religion in the world, with around 2.5 billion believers. In the second place was Islam, with around 1.9 billion adherents.

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.

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.

Census: Population: by Religion: Christian: Haryana data was reported at 50,353.000 Person in 03-01-2011. This records an increase from the previous number of 27,185.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Haryana data is updated decadal, averaging 38,769.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 50,353.000 Person in 03-01-2011 and a record low of 27,185.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Haryana 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: Karnataka data was reported at 1,142,647.000 Person in 03-01-2011. This records an increase from the previous number of 1,009,164.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Karnataka data is updated decadal, averaging 1,075,905.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 1,142,647.000 Person in 03-01-2011 and a record low of 1,009,164.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Karnataka 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: Other Religion and Persuasions: Goa data was reported at 258.000 Person in 03-01-2011. This records a decrease from the previous number of 353.000 Person for 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Goa data is updated decadal, averaging 305.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 353.000 Person in 03-01-2001 and a record low of 258.000 Person in 03-01-2011. Census: Population: by Religion: Other Religion and Persuasions: Goa 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.GAE008: Census: Population: by Religion: Other Religion and Persuasions.

Among the people surveyed in 26 countries around the world, a slight majority of the baby boomer generation were Christians. By comparison, only 42 percent of Generation Z stated that they were Christians. Millennials was the generation with the highest share of people stating that they had a religious belief other than Islam and Christianity.

Census: Population: by Religion: Christian: Tripura data was reported at 159,882.000 Person in 03-01-2011. This records an increase from the previous number of 102,489.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Tripura data is updated decadal, averaging 131,185.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 159,882.000 Person in 03-01-2011 and a record low of 102,489.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Tripura 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: Rural data was reported at 103,504,739.000 Person in 2011. This records an increase from the previous number of 88,794,744.000 Person for 2001. India Census: Population: by Religion: Muslim: Rural data is updated yearly, averaging 96,149,741.500 Person from Mar 2001 (Median) to 2011, with 2 observations. The data reached an all-time high of 103,504,739.000 Person in 2011 and a record low of 88,794,744.000 Person in 2001. India Census: Population: by Religion: Muslim: Rural 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.

Census: Population: by Religion: Other Religion and Persuasions: Punjab data was reported at 10,886.000 Person in 03-01-2011. This records an increase from the previous number of 8,594.000 Person for 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Punjab data is updated decadal, averaging 9,740.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 10,886.000 Person in 03-01-2011 and a record low of 8,594.000 Person in 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: 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.GAE008: Census: Population: by Religion: Other Religion and Persuasions.

Census: Population: by Religion: Other Religion and Persuasions: Uttarakhand data was reported at 993.000 Person in 03-01-2011. This records an increase from the previous number of 770.000 Person for 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Uttarakhand data is updated decadal, averaging 881.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 993.000 Person in 03-01-2011 and a record low of 770.000 Person in 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Uttarakhand 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.GAE008: Census: Population: by Religion: Other Religion and Persuasions.

Census: Population: by Religion: Other Religion and Persuasions: Lakshadweep data was reported at 7.000 Person in 03-01-2011. This records an increase from the previous number of 0.000 Person for 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Lakshadweep data is updated decadal, averaging 3.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 7.000 Person in 03-01-2011 and a record low of 0.000 Person in 03-01-2001. Census: Population: by Religion: Other Religion and Persuasions: Lakshadweep 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.GAE008: Census: Population: by Religion: Other Religion and Persuasions.

Census: Population: by Religion: Hindu: Andaman and Nicobar Islands data was reported at 264,296.000 Person in 03-01-2011. This records an increase from the previous number of 246,589.000 Person for 03-01-2001. Census: Population: by Religion: Hindu: Andaman and Nicobar Islands data is updated decadal, averaging 255,442.500 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 264,296.000 Person in 03-01-2011 and a record low of 246,589.000 Person in 03-01-2001. Census: Population: by Religion: Hindu: Andaman and Nicobar Islands 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.GAE002: Census: Population: by Religion: Hindu.

According to a 2016 survey, Muslim men and women above the age of 20 years are to the same extend religious. In contrast, Christian and Buddhist women are more religious than Christian and Buddhist men.

Census: Population: by Religion: Christian: Lakshadweep: Male data was reported at 286.000 Person in 03-01-2011. This records a decrease from the previous number of 422.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Lakshadweep: Male data is updated decadal, averaging 354.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 422.000 Person in 03-01-2001 and a record low of 286.000 Person in 03-01-2011. Census: Population: by Religion: Christian: Lakshadweep: 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.GAE004: Census: Population: by Religion: Christian.

Census: Population: by Religion: Christian: Andaman and Nicobar Islands data was reported at 80,984.000 Person in 03-01-2011. This records an increase from the previous number of 77,178.000 Person for 03-01-2001. Census: Population: by Religion: Christian: Andaman and Nicobar Islands data is updated decadal, averaging 79,081.000 Person from Mar 2001 (Median) to 03-01-2011, with 2 observations. The data reached an all-time high of 80,984.000 Person in 03-01-2011 and a record low of 77,178.000 Person in 03-01-2001. Census: Population: by Religion: Christian: Andaman and Nicobar Islands 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.