The percentage of the worlds population that identifies as atheist varies depending on the source and definition of atheism. According to reports from the Worldwide Independent Network/Gallup International Association's four global polls, the percentage of people who identify as "convinced atheists" ranges from 4% in 2005 to 9% in 2017. The Pew Research Centre reports that in 2012, 16% of the world's population was "religiously unaffiliated," which includes atheists, agnostics, and people who do not identify with any particular religion in surveys. However, many people in this category may still hold some religious beliefs and engage in religious practices.
Different sources report different percentages of atheists in different countries. For example, a 2017 poll by Gallup International and the Worldwide Independent Network of Market Research (WIN) found that China has the highest percentage of atheists at 91%, followed by Japan at 87%, Sweden at 78%, and the Czech Republic at 76% . Another estimate by Colin Mathers in 2020 found that China has the highest proportion of atheists at 79%, followed by the Czech Republic at 70%, Sweden at 68%, and Estonia at 64% .
Overall, it is difficult to accurately estimate the exact number of atheists in a given country or in the world. According to the Oxford Handbook of Atheism, atheists make up about 7% of the world's population.
