Islam is the largest religion in Indonesia, with 87.06% of the Indonesian population identifying themselves as Muslims, based on civil registry data in 2023. In terms of denomination, the overwhelming majority are Sunni and non-denominational Muslims; the Pew Research Center estimates them as comprising ~99% of the country's Muslim population in 2011, with the remaining 1% being Shia, who are concentrated around Jakarta, and about 400,000 Ahmadi as well.