Measured global religious composition, 2010-2020
Pew Research Center's June 2025 study of change between 2010 and 2020 found Christians at 28.8% of world population (about 2.3 billion, down 1.8 points as a share) and Muslims at 25.6% (up 1.8 points, an increase of about 347 million people). The distribution these figures describe still corresponds visibly to the historical routes: Islam concentrated along the Indian Ocean rim and the old caravan belt, Christianity across the Mediterranean, European colonial reach and sub-Saharan Africa.
Observed — measured or witnessed, with the observation cited.
Subjects
- Christianity · belief_system · Mediterranean, Near East, and subsequently global · not located
- Islam · belief_system · not located
- Hinduism · belief_system · South Asia, with historical extension into Southeast Asia · not located
- Judaism · belief_system · Levant, with diaspora across the Mediterranean, Near East and beyond · not located
- Indian Ocean maritime trade network · route · Indian Ocean rim: East Africa, Arabia, South Asia, Southeast Asia · not located
Evidence
Partly verified — Core facts are sourced; some optional detail is deliberately absent.
The World's Religious Groups: How Their Sizes Changed from 2010 to 2020
Between 2010 and 2020 Christians fell 1.8 percentage points to 28.8% of world population (about 2.3 billion, an absolute rise of 122 million) while Muslims rose 1.8 points to 25.6% (an absolute rise of 347 million); Christians remained the largest group and Muslims the fastest-growing.
Pew Research Center · 9 June 2025 · Partly verified
Pew Research Center, 'How the Global Religious Landscape Changed from 2010 to 2020', released 9 June 2025 — https://www.pewresearch.org/religion/2025/06/09/how-the-global-religious-landscape-changed-from-2010-to-2020/