Estimates of Pentecostal and charismatic Christians run from about five hundred million to over six hundred million, or roughly a quarter of all Christians. The range is wide because the category is not a denomination and the counting rules differ: the larger figures include charismatic Catholics and charismatics inside mainline Protestant churches, who have never left their own communions.
This is the form of Christianity that has grown fastest anywhere in the last century. Brazil, Nigeria, sub-Saharan Africa generally, the Philippines, Indonesia, China and Central America hold the bulk of it. In Latin America the growth has come very largely at the expense of Catholicism; in Africa it overlaps with the African-initiated churches, which are indigenous foundations answering to no Western body.
Three features of the current landscape are worth stating plainly and without judgement. The movement is heavily entrepreneurial: large congregations are frequently founded by and identified with a single leader, and succession is often familial, which produces both rapid growth and recurrent governance crises. The prosperity gospel, the teaching that faith and giving produce material return, is widespread in parts of the movement and is criticised sharply from within it as well as from outside. And Pentecostal churches have become significant political actors, most visibly in Brazil, Nigeria, Guatemala and Kenya, where evangelical caucuses now shape national politics directly.
The classic dispute with the rest of Protestantism remains open: whether the miraculous gifts continued past the apostolic age. Pentecostals say they did. Cessationists say they did not. Neither position has moved much in a century, but the demographic weight behind the first has shifted enormously.