Nairobi
696 km²
San Francisco
121 km²
Kenya
USA
Area Comparison
Nairobi is 5.8x larger than San Francisco
Population Comparison
Nairobi has 5.4x more people than San Francisco
Nairobi is significantly larger, covering 5.8 times the area of San Francisco. Nairobi spans 696 km² (269 mi²) while San Francisco covers 121 km² (47 mi²) — a difference of 575 km². You could fit San Francisco inside Nairobi approximately 5 times.
To put Nairobi's size in perspective, its area of 696 km² is about 1.1x smaller than New York City. Meanwhile, San Francisco at 121 km² is about 1.2x the size of Paris (city proper).
In more relatable units, Nairobi's 696 km² is about 97,000 American football fields, 12 times the area of Manhattan, or 7 times the area of Paris. For San Francisco, that's about 17,000 American football fields, 60 times the area of Monaco, or 35 times the area of Central Park.
Nairobi is the capital and largest city of Kenya, located in the south-central part of the country. As of 2024, it has a population of 4.8 million and a metropolitan population of 5.7 million, making it the 11th most populous city in Africa. Nicknamed the "Green City under the Sun", Nairobi is uniquely notable for being the only capital city in the world that hosts a national park within its boundaries. Its name originates from the Maasai phrase Enkare Nyirobi, meaning "place of cool waters".
Known as "Green City under the Sun", Nairobi covers 696 km² with a population of 4.7 million. The city was established in 1899. Nairobi is known for Nairobi National Park, Giraffe Centre, Karen Blixen Museum, among other attractions. The city's main transit system is the Nairobi Commuter Rail.
Nairobi is the only capital city in the world that hosts a national park within its boundaries.
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.
Looking beyond city limits, the San Francisco metropolitan area covers 6,984 km², which is 10.0x larger than greater Nairobi at 696 km². The Nairobi metro area is also more populous, with 4.7 million people compared to 4.7 million.
Nairobi has a population density of 6,796 people per km² — a densely populated city. San Francisco, with 7,190 people per km², is a densely populated city. Both cities have comparable density, though San Francisco is slightly more compact.
This comparison spans continents — Nairobi in Africa versus San Francisco in North America. Despite the geographic distance, comparing their sizes reveals surprising insights about how cities grow worldwide.
Nairobi has a subtropical highland climate while San Francisco experiences Mediterranean conditions. When it's noon in Nairobi, it's 1:00 AM in San Francisco — a 11-hour time difference.
Size Ratio
San Francisco fits inside Nairobi ~5 times
Time Difference
11 hours apart
History
San Francisco is ~123 years older
Nairobi covers 696 km². Cities with a similar urban footprint include Tehran (730 km²), Jakarta (662 km²), Singapore (733 km²), Bangalore (741 km²), or Hyderabad (650 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 Nairobi to San Francisco is 15,437 km (9,592 miles), with an estimated flight time of ~18h 40m.
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