Gebze's 2025 population is now estimated at 846,841. In 1950, the population of Gebze was 4,433. Gebze has grown by 15,481 in the last year, which represents a 1.86% annual change.These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Gebze, which typically includes Gebze's population in addition to adjacent suburban areas.