World Christian Database (Brill, 2007, updated quarterly)
Designed for both the casual user and research scholar, the World Christian Database (WCD) is an online database containing comprehensive demographic statistics on global Christianity. Over 400 categories of information including religious adherents, Christian traditions and missions trends are available at the province, country, people group, language and city levels for the entire world. The full-time staff at The Center for the Study of Global Christianity is dedicated to updating and maintaining the WCD. New information from thousands of sources is reviewed on a weekly basis to continually refine and improve the WCD. Documents describing World Christian Database Sources and Methodology: World Christian Database Sources, Word Christian Database Methodology.
World Religion Database (Brill, 2008, updated quarterly)
The World Religion Database (WRD), edited by Todd Johnson and Brian Grim, contains detailed statistics on religious affiliation for every country in the world. It is the major source to render a definitive picture of international religious demography. The WRD provides both current and historical data, as well as sophisticated forecasts of future developments. For each of the world’s religions, best estimates at multiple dates for the period 1900 to 2050 are given. The WRD also offers access to the sources which underlie the figures in the database, such as censuses and surveys. Through an interactive feedback mechanism users can leave comments on sources or methodology related to any figure reported in the WRD. The WRD is constantly updated with new sets of data as they become available, such as estimates of religious affiliation at the province level and religious freedom information for all countries in the world. No other database available today is as comprehensive. Click here for more information, or to access the World Religion Database.