The global Muslim population has undergone a remarkable demographic transformation over the past decade, positioning Islam as the fastest-growing religion in the world. According to a new report released by the Pew Research Center on June 9, 2025, the number of Muslims grew by more than 350 million people from 2010 to 2020-outpacing all other major religious groups.
This increase has not only boosted Islam's global share of the population but is also reshaping religious and cultural landscapes in every region of the world.
A Decade of Rapid Growth
Between 2010 and 2020, the global Muslim population expanded from 1.6 billion to 1.9 billion, a 21% increase, compared to a 10% growth rate among all non-Muslims. Today, Muslims make up approximately 26% of the global population, up from 24% a decade earlier.
No other religious group experienced this level of growth during the same period. The increase in the Muslim population (+347 million) far exceeded that of Christians (+122 million), Hindus (+80 million), and unaffiliated individuals (+72 million).
Regional Shifts and Concentrations
Where Most Muslims Live
The world's largest Muslim populations are concentrated in a few key countries:
What's Fueling the Growth?
1. High Fertility Rates
Muslims have the highest fertility rate of any major religious group. In regions such as Sub-Saharan Africa and South Asia, Muslim families tend to have more children on average compared to non-Muslims-resulting in rapid generational growth.
2. Young Age Structure
Globally, Muslims have a median age that is younger than that of any other major faith group, which means a larger proportion of Muslims are entering their childbearing years each decade.
3. Migration
Migration has significantly boosted the Muslim population in North America and Europe. The Syrian civil war, political instability in Afghanistan, and economic migration from South Asia have contributed to a large influx of Muslim refugees and workers, especially between 2014 and 2018.
4. Conversions to Islam
Although conversions are not the primary driver of global Muslim population growth, they still play a notable role-particularly in the United States and Europe. Pew data shows that Islam gains more converts than it loses in North America, where an estimated 23% of American Muslim adults are converts to the faith. Most conversions are motivated by spiritual conviction, marriage, or social justice concerns.
Globally, conversions are net-positive for Islam, even if their impact is modest compared to birth rates. By contrast, some other religious groups-particularly Christianity in Western countries-tend to see a net loss due to conversion trends.
Looking Ahead: Islam and the Future of Faith
According to Pew Research projections, Islam is poised to become the world's largest religion by the second half of the 21st century. If current trends continue, the Muslim share of the global population will continue to rise steadily, while the Christian share may plateau.
This demographic momentum has deep implications for geopolitics, social policy, interfaith relations, and cultural identity across the globe. As younger Muslim populations come of age, and diasporas strengthen their presence in Western societies, the influence of Islam-culturally, spiritually, and politically-is set to grow.
Full Report
For detailed statistics, maps, and regional insights, read the full Pew Research Center study.