The following sites are helpful for identifying statistical information about religion, both domestic and international.
This is a growing collection of over 41,000 adherent statistics and religious geography citations, including references to published membership/adherent statistics and congregation statistics for over 4,200 religions, churches, denominations, religious bodies, faith groups, tribes, cultures, movements, ultimate concerns, etc. Data are from both primary research sources such as government census reports, statistical sampling surveys and organizational reporting, as well as citations from secondary literature which mention adherent statistics.
- American Religion Data Archive
The ARDA provides quantitative data on American religion, including data on churches and church membership, religious professionals, and religious groups (individuals, congregations and denominations).
- American Religious Identification Survey
This survey was conducted by The Graduate Center at The City University of New York. There are 15 exhibits (charts) describing the way Americans feel about various religions, how their outlook has changed, plus age, gender, race, ethnicity, and membership statistics, and a comparison with the results of a similar survey taken in 1990. The results are summarized in a Key Findings section.
- CIA World Factbook
This publication, updated yearly, by the Central Intelligence Agency (CIA) gives an ordered listing of religions by adherents starting with the largest group and sometimes includes the percent of total population. It is a surprising but helpful source of information.
- ICPSR (Inter-university Consortium for Political and Social Research)
- International Religious Freedom Report
Submitted to the Congress by the Department of State, this report supplements the most recent Human Rights Reports by providing additional detailed information with respect to matters involving international religious freedom.
- National Congregations Study
This study, conducted in 1998 and 2006, collected social, structural, composition, activity, and programming data from 1236 congregations.
- North America Jewish Data Bank
The North American Jewish Data Bank is the central repository of social scientific studies of North American Jewry. The Data Banks primary functions are to (1) acquire, archive, and disseminate quantitative data sets and reports, both contemporary and historical, and (2) encourage utilization of the archive through training and provide information about methods for studying Jewish communities.
- Pew Forum on Religion and Public Life
This group seeks to understand the interaction of religion and public affairs. They have a number of surveys and publications analyzing these interactions.
- Social Explorer
Explore congregational membership in every county, state and the United States. These data are based on the Religious Congregations and Membership Study, and delivered in partnership with The ARDA organization. Congregational membership data are collected by representatives of the Association of Statisticians of American Religious Bodies (ASARB).
- Statistical Abstract of the United States
This publication produced yearly by the United States Bureau of Census provides selected statistics on religion in the United States.
- Pluralism Project
This project, based at Harvard University, seeks to help Americans engage with the realities of religious diversity through research, outreach, and the active dissemination of resources. They have a helpful collection of statistics and resources on various religious traditions.
- U.S. Congregational Life Survey: A National and International Study of Congregations
This survey was designed to help churches create profiles of their congregations, also presents an overall picture of church attendees and participation. The site reports key overall results, not results of specific churches or denominations.
- World Christian Database
This database provides comprehensive statistical information on world religions, Christian denominations, and people groups. Data are available on 9,000 Christian denominations, 13,000 ethnolinguistic peoples, as well as data on 5,000 cities, 3,000 provinces and 238 countries. It was formerly under the auspices of Gordon-Conwell Theological Seminary, but is now adminstered by another entity. A companion print reference volume is also available. The statistics provided in this database are at times questionable in their reliability.