Buenos Aires
203 km²
San Francisco
121 km²
Argentina
USA
Area Comparison
Buenos Aires is 1.7x larger than San Francisco
Population Comparison
Buenos Aires has 3.5x more people than San Francisco
Buenos Aires is significantly larger, covering 1.7 times the area of San Francisco. Buenos Aires spans 203 km² (78 mi²) while San Francisco covers 121 km² (47 mi²) — a difference of 82 km².
To put Buenos Aires's size in perspective, its area of 203 km² is roughly the same size as Amsterdam. Meanwhile, San Francisco at 121 km² is about 1.2x the size of Paris (city proper).
Picture Buenos Aires another way: its area is large enough to fit about 28,000 American football fields, 100 times the area of Monaco, or 60 times the area of Central Park. San Francisco, by comparison, equals about 17,000 American football fields, 60 times the area of Monaco, or 35 times the area of Central Park.
Buenos Aires, officially the Autonomous City of Buenos Aires, is the capital and largest city of Argentina. It is located on the southwest of the Río de la Plata. Buenos Aires is classified as an Alpha− global city, according to the GaWC 2024 ranking. The city proper has a population of 3.1 million and its urban area has a population of 16.7 million, making it the 21st most populous metropolitan area in the world.
Known as "Paris of South America", Buenos Aires covers 203 km² with a population of 3.1 million. The city was established in 1536. Buenos Aires is known for La Boca's Caminito, Recoleta Cemetery, Teatro Colón, among other attractions. The city's main transit system is the Buenos Aires Subte.
Buenos Aires is classified as an Alpha− global city according to the GaWC 2024 ranking.
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.
Also known as "The City by the Bay", San Francisco has an area of 121 km² and is home to 0.9 million people. It was established in 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 1.5x larger than greater Buenos Aires at 4,758 km². The Buenos Aires metro area is also more populous, with 15.2 million people compared to 4.7 million.
Buenos Aires has a population density of 15,074 people per km² — an extremely dense urban environment. San Francisco, with 7,190 people per km², is a densely populated city. Buenos Aires is noticeably denser, packing 2.1 times more people per square kilometer.
This comparison spans continents — Buenos Aires in South America versus San Francisco in North America. Despite the geographic distance, comparing their sizes reveals surprising insights about how cities grow worldwide.
Buenos Aires has a humid subtropical climate while San Francisco experiences Mediterranean conditions. When it's noon in Buenos Aires, it's 7:00 AM in San Francisco — a 5-hour time difference.
Density Gap
Buenos Aires is 2.1x more densely populated
Time Difference
5 hours apart
History
Buenos Aires is ~240 years older
Buenos Aires covers 203 km². Cities with a similar urban footprint include Helsinki (214 km²), Amsterdam (219 km²), Stockholm (188 km²), Osaka (225 km²), or Boston (232 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 Buenos Aires to San Francisco is 10,410 km (6,468 miles), with an estimated flight time of ~12h 45m.
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