Calamba's 2021 population is now estimated at 539,157. In 1950, the population of Calamba was 41,121. Calamba has grown by 14,580 since 2015, which represents a 2.78% 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 Calamba, which typically includes Calamba's population in addition to adjacent suburban areas.