List of countries by irreligion

Irreligion, which may include deism, agnosticism, ignosticism, anti-religion, atheism, skepticism, ietsism, spiritual but not religious, freethought, anti-theism, apatheism, non-belief, pandeism, secular humanism, non-religious theism, pantheism and panentheism, varies in the countries around the world. According to reports from the Worldwide Independent Network/Gallup International Association's (WIN/GIA) four global polls: in 2005, 77% were a religious person and 4% were "convinced atheists" while in 2012, 23% were not a religious person and an additional 13% were "convinced atheists"; in 2015, 22% were not a religious person and an additional 11% were "convinced atheists"; and in 2017, 25% were not a religious person and an additional 9% were "convinced atheists".
According to sociologist Phil Zuckerman, broad estimates of those who have an absence of belief in a god range from 500 to 750 million people worldwide. According to sociologists Ariela Keysar and Juhem Navarro-Rivera's review of numerous global studies on atheism, there are 450 to 500 million positive atheists and agnostics worldwide (7% of the world's population), with China having the most atheists in the world (200 million convinced atheists).
Methods.
Each poll uses different questions and methods:-
The numbers come from different years, and might not be accurate for countries with governments that require or urge religion or secularism.
Countries and regions.
The WIN-Gallup International Association (WIN/GIA) poll results below are the totals for "not a religious person" and "a convinced atheist" combined. Keysar et al. have advised caution with WIN/Gallup International figures since more extensive surveys which have used the same wording for decades and have bigger sample sizes, have consistently reached lower figures. For example, the WIN/GIA numbers from China were overestimated which in turn inflated global totals.
By population as of 2004.
Countries with the greatest number of people without religion (atheists and agnostics), based on the total population of each country as of 2004 and the percentage of non-religious people according to Zuckerman: