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Islam is the name of the religion. Muslim is the name given to its practitioners.



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June 10, 2025


Islam was the world’s fastest-growing religion from 2010 to 2020
By
Conrad Hackett

Muslims grew faster than any other major religious group in the decade leading up to 2020, according to new Pew Research Center estimates. Muslims continued to be the second-largest religious group in the world after Christians.

From 2010 to 2020, the number of Muslims increased by 347 million people to 2.0 billion people. Christians grew by 122 million to 2.3 billion. Buddhists are the only group in our analysis that shrank in absolute numbers, by 19 million people, to 324 million.
A bar chart showing that the Muslim population increased more than any other religion from 2010 to 2020.

Our estimates covered 201 countries and territories that are home to 99.98% of the world’s population. We focused on seven groups of people: Christians, Muslims, Hindus, Buddhists, Jews, adherents of all other religions, and people who do not identify with any religion.

Muslims added more people during the decade (347 million) than all non-Muslim religions combined (248 million). In fact, the growth in the Muslim population exceeded the total number of Buddhists worldwide in 2020 (324 million).

As a result of the rapid growth of the Muslim population, the gap between the global number of Muslims and Christians is shrinking. In 2010, Muslims made up 23.9% of the world’s population and Christians accounted for 30.6%. By 2020, Muslims accounted for 25.6% and Christians 28.8%. Growth in the number of Christians was slowed by high rates of disaffiliation.

https://www.pewresearch.org/short-reads/2025/06/10/islam-was-the-worlds-fastest-growing-religion-from-2010-to-2020/