According to the South African National Census of 2011, the population of the City of Cape Town metropolitan municipality – an area that includes suburbs and exurbs not always considered as part of Cape Town – is 3,740,026 people. This represents an annual growth rate of 2.6% compared to the results of the previous census in 2001 which found a population of 2,892,243 people.
The sex ratio is 96, meaning that there are slightly more women than men. 42.4% of the population described themselves as "Coloured", 15.7% as "White", 38.6% as "Black African", and 1.4% as "Indian or Asian". In 1944, 47% of the city's population was White, 46% was Coloured, less than 6% was Black African and 1% was Asian. Of those residents who were asked about their first language, 35.7% spoke Afrikaans, 29.8% spoke Xhosa and 28.4% spoke English. 24.8% of the population is under the age of 15, while 5.5% is 65 or older.
Of those residents aged 20 or older, 1.8% have no schooling, 8.1% have some schooling but did not finish primary school, 4.6% finished primary school but have no secondary schooling, 38.9% have some secondary schooling but did not finish Grade 12, 29.9% finished Grade 12 but have no higher education, and 16.7% have higher education. Overall, 46.6% have at least a Grade 12 education. Of those aged between 5 and 25, 67.8% are attending an educational institution. Amongst those aged between 15 and 65 the unemployment rate is 23.7%. The average annual household income is R161,762.
There are 1,068,573 households in the municipality, giving an average household size of 3.3 people. Of those households, 78.4% are in formal structures (houses or flats), while 20.5% are in informal structures (shacks). 94.0% of households use electricity for lighting. 87.3% of households have piped water to the dwelling, while 12.0% have piped water through a communal tap. 94.9% of households have regular refuse collection service. 91.4% of households have a flush toilet or chemical toilet, while 4.5% still use a bucket toilet. 82.1% of households have a refrigerator, 87.3% have a television and 70.1% have a radio. Only 34.0% have a landline telephone, but 91.3% have a cellphone. 37.9% have a computer, and 49.3% have access to the Internet (either through a computer or a cellphone).