Johannesburg
1,644 km²
San Francisco
121 km²
South Africa
USA
Area Comparison
Johannesburg is 13.6x larger than San Francisco
Population Comparison
Johannesburg has 5.5x more people than San Francisco
In terms of area, Johannesburg is 13.6x the size of San Francisco. Johannesburg spans 1,644 km² (635 mi²) while San Francisco covers 121 km² (47 mi²) — a difference of 1,523 km². You could fit San Francisco inside Johannesburg approximately 13 times.
To put Johannesburg's size in perspective, its area of 1,644 km² is roughly the same size as London. Meanwhile, San Francisco at 121 km² is about 1.2x the size of Paris (city proper).
Johannesburg's footprint is roughly about 230,000 American football fields, 28 times the area of Manhattan, or 16 times the area of Paris — pick whichever unit feels intuitive. San Francisco works out to about 17,000 American football fields, 60 times the area of Monaco, or 35 times the area of Central Park.
Johannesburg, colloquially known as Jozi, Joburg or "The City of Gold", is the most populous city in South Africa. The City of Johannesburg itself has a population of 5,538,596, while the City of Johannesburg Metropolitan Municipality has a population of 6,599,190, making it one of the 100 largest urban areas in the world. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, and seat of the country's highest court, the Constitutional Court.
Known as "Jozi", Johannesburg covers 1,644 km² with a population of 4.8 million. The city was established in 1886. Johannesburg is known for Apartheid Museum, Soweto township, Constitutional Court, among other attractions.
Johannesburg ranks among the world's 100 largest urban areas, with a metro population of about 6.6 million.
San Francisco, officially the City and County of San Francisco, is the fourth-most populous city in California and the 17th-most populous in the United States, with a population of 826,079 in 2025. Among U.S. cities with a population of 300,000 or more, San Francisco is ranked first by per capita income, second by population density, and sixth by aggregate income as of 2023.
Nicknamed "The City by the Bay", San Francisco has an area of 121 km² and is home to 0.9 million people. The city dates back to 1776. Visitors come for Golden Gate Bridge, Alcatraz Island, Cable cars, and much more. Getting around is easy with the BART & Muni.
San Francisco ranks first by per capita income among all US cities with 300,000+ residents as of 2023.
Johannesburg has a population density of 2,920 people per km² — a moderately dense city. San Francisco, with 7,190 people per km², is a densely populated city. San Francisco is noticeably denser, packing 2.5 times more people per square kilometer.
Size Ratio
San Francisco fits inside Johannesburg ~13 times
Density Gap
San Francisco is 2.5x more densely populated
History
San Francisco is ~110 years older
Johannesburg covers 1,644 km². Cities with a similar urban footprint include Bogotá (1,578 km²), London (1,572 km²), Bangkok (1,569 km²), Houston (1,725 km²), or São Paulo (1,521 km²).
San Francisco covers 121 km². Cities with a similar urban footprint include Vancouver (115 km²), Paris (105 km²), Miami (143 km²), Barcelona (101 km²), or Lisbon (100 km²).
The straight-line distance from Johannesburg to San Francisco is 16,964 km (10,541 miles), with an estimated flight time of ~20h 27m.
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