The U.S. government estimates the total population at 262.8 million (July 2018 estimate).  According to the 2010 census, approximately 87 percent of the population is Muslim, 7 percent Protestant, 3 percent Roman Catholic, and 1.5 percent Hindu.  Those identifying with other religious groups, including Buddhism, traditional indigenous religions, Confucianism, and other Christian denominations, and those who did not respond to the census question comprise approximately 1.3 percent of the population.

The Muslim population is overwhelmingly Sunni.  An estimated one to three million Muslims are Shia.  Many smaller Muslim groups exist; estimates put the total number of Ahmadi Muslims at 200,000 to 400,000.

Many religious groups incorporate elements of Islam, Hinduism, and Buddhism, making it difficult to disaggregate the exact number of followers.  An estimated 20 million people, primarily in Java, Kalimantan, and Papua, practice various traditional belief systems, often referred to collectively as aliran kepercayaan.  There are approximately 400 different aliran kepercayaan communities throughout the archipelago.

There is a Sikh population estimated at between 10,000 and 15,000, with approximately 5,000 in Medan and the rest in Jakarta.  There are very small Jewish communities in Jakarta, Manado, Jayapura, and elsewhere.  The Baha’i Faith and Falun Dafa (or Falun Gong) communities report thousands of members, but independent estimates are not available.  The number of atheists is also unknown, but the group Indonesian Atheists states it has more than 700 members.

The province of Bali is predominantly Hindu, and the provinces of Papua, West Papua, East Nusa Tenggara, and North Sulawesi are predominantly Christian.

The U.S. government estimates the total population at 207.9 million (July 2018 estimate).  According to the provisional results of a national census conducted in 2017, 96 percent of the population is Muslim.  According to government figures, the remaining 4 percent includes Ahmadi Muslims (whom Pakistani law does not recognize as Muslim), Hindus, Christians, Parsis/Zoroastrians, Baha’is, Sikhs, Buddhists, Kalash, Kihals, and Jains.  Most of the historic Jewish community has emigrated.

Sources vary on the precise breakdown of the Muslim population between Sunni and Shia Muslims.  Sunnis are generally believed to be 80-85 percent of the Muslim population and Shia are generally believed to make up 15-20 percent.  Unofficial estimates vary widely with regard to the size of minority religious groups.  According to 2014 media accounts, although there are 2.9 million non-Muslims registered with the National Database and Registration Authority (NADRA), the actual number exceeds 3.5 million.  Religious community representatives estimate minority religious groups constitute 3 to 5 percent of the population.

According to the 2014 government registration documents cited by the press, there are approximately 1.4 million Hindus, 1.3 million Christians, 126,000 Ahmadis, 34,000 Baha’is, 6,000 Sikhs, and 4,000 Parsis.  Taking account of the Ahmadi boycott of the official census, however, community sources put the number of Ahmadi Muslims at approximately 500,000-600,000.  Estimates of the Zikri Muslim community, located in Balochistan, range between 500,000 and 800,000 individuals.  Several minority rights advocacy groups dispute the provisional results of the 2017 census and state the numbers underrepresent their true population.

The U.S. government estimates the total population at 81.3 million (July 2018 estimate).  According to the Turkish government, 99 percent of the population is Muslim, approximately 77.5 percent of which is Hanafi Sunni.  Representatives of other religious groups estimate their members represent 0.2 percent of the population, while the most recent published surveys suggest approximately 2 percent of the population is atheist.

Alevi foundation leaders estimate Alevis comprise 25 to 31 percent of the population; Pew Research Center reporting indicates five percent of Turkish Muslims state they are Alevis.  The Shia Jafari community estimates its members make up 4 percent of the population.

Non-Muslim religious groups are mostly concentrated in Istanbul and other large cities as well as in the southeast.  Exact figures are not available; however, these groups self-report approximately 90,000 Armenian Apostolic Orthodox Christians (including migrants from Armenia); 25,000 Roman Catholics (including migrants from Africa and the Philippines); and 16,000 Jews.  There are also approximately 25,000 Syrian Orthodox Christians (also known as Syriacs); 15,000 Russian Orthodox Christians (mostly immigrants from Russia who hold residence permits); and 10,000 Baha’is.

Other groups include fewer than 1,000 Yezidis; 5,000 Jehovah’s Witnesses; 7,000 members of Protestant denominations; fewer than 3,000 Chaldean Christians; and up to 2,000 Greek Orthodox Christians.  There also are small, undetermined numbers of Bulgarian Orthodox, Nestorian, Georgian Orthodox, Ukrainian Orthodox, Syriac Catholic, Armenian Catholic, and Maronite Christians.  The Church of Jesus Christ of Latter-day Saints estimates its membership at 300 individuals.