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Before we get to the numbers and percentages, let’s cover some quick definitions. An atheist is someone who doesn’t believe in the existence of God or gods. An agnostic is someone who isn’t sure if there is a God or not, or who doesn’t feel like he or she (or anyone) can have any valid information on the matter, and thus, thinks that it is impossible to say there is a God, or that there isn’t. Both atheists and agnostics are non-theists: they lack a belief in a deity. So how many people are we talking here? A lot.
According to the latest international survey data, as reported by Ariela Keysar and Juhem Navarro-Rivera in the recently published Oxford Handbook of Atheism, there are approximately 450-500 million non-believers in God worldwide, which amounts to about 7% of the global adult population. And according to the Pew Research Center, if we broaden the category to include all non-religious people in general—those unaffiliated adults who do not identify with any religion—we’re talking 1.1 billion people, which equals about 16.5% of the global adult population. As such, “non-religious” is actually the third largest “religion” in the world, coming only behind Christianity (in first place) and Islam (in second). Thus, there are more secular men and women on planet earth—many of whom are atheists and agnostics—than there are Hindus, Buddhists, Mormons, Sikhs, Jains, or Jews.
But let’s look at the number of non-theists (atheists and agnostics) specifically.
Various selected countries, according to the Oxford Handbook, with the highest percentages of non-believers, include:
- Czech Republic: 55% atheist/agnostic (actual number: 4,649,620)
- France: 41% (19,965,630)
- Sweden: 39% (2,800,152)
- Germany: 36% (24,564,226)
- Netherlands: 34% (4,303,110)
- Belgium: 34% (2,857,053)
- Denmark: 32% (1,369,512)
- Norway: 32% (1.146,464)
- United Kingdom: 30% (14,579,992)
- South Korea: 28% (10,419,885)
- New Zealand: 28% (866,000)
- Finland: 28% (1,172,404)
- Japan: 28% (29,766,356)
- Hungary: 27% (2,254,556)
- Australia: 26% (5,058,772)
- Spain: 21% (7,633,561)
- China: 17.9% (234,595,000)
- Russia: 17% (18,971,229)
- Taiwan: 15% (2,665,188)
- Uruguay: 14% (232,018)
- Italy: 13% (6,648,003)
- Israel: 11% (524,780)
- Ireland: 10% (369,949)
- United States: 8% (18,625,556)
- Mexico: 6% (3,685,552)
- India: 2.5% (27,691,000)
There are many additional countries with significantly high percentages of atheism and agnosticism, such as Estonia, Slovenia, Vietnam, etc., and many more countries where the percentages are quite low (1%-2%), but such countries can often be highly populated, such as Brazil, so that 1.2% atheist/agnostic still equals over two million Brazilian non-believers.
Also, these numbers and percentages are most likely fairly conservative, because in many countries, being a non-believer in God is highly stigmatized and/or illegal, so people are more likely to hide their lack of faith, rather than proclaim it to some person doing a survey.
What are we to make of these hundreds of millions of atheists and agnostics? That is a wide-open question, to be sure. But according to various sociological, anthropological, and psychological studies, the following generalizations are valid: men are more likely to be non-theists than women (on average), non-theism is strongest in Europe and the Anglophone world, most societies with the highest percentages of atheists and agnostics are faring relatively well (so the fear that secularism is somehow dangerous to society is clearly unfounded), and non-theists tend to be more highly educated and intellectually oriented (on average) than their believing peers.
But perhaps the most significant matter concerning non-believers is that they generally have far fewer children than religious people—so the future of atheism and agnosticism may not be as bright as it is for the religious, especially Muslims, who tend to have the most children of all.
