San Diego
964 km²
San Francisco
121 km²
United States
USA
Area Comparison
San Diego is 8.0x larger than San Francisco
Population Comparison
San Diego has 1.6x more people than San Francisco
Yes — San Diego is 8.0x larger than San Francisco by area. San Diego spans 964 km² (372 mi²) while San Francisco covers 121 km² (47 mi²) — a difference of 843 km². You could fit San Francisco inside San Diego approximately 7 times.
To put San Diego's size in perspective, its area of 964 km² is roughly the same size as Berlin. Meanwhile, San Francisco at 121 km² is about 1.2x the size of Paris (city proper).
San Diego's footprint is roughly about 135,000 American football fields, 16 times the area of Manhattan, or 9 times the area of Paris — pick whichever unit feels intuitive. 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.
San Diego is a city on the Pacific coast of Southern California, adjacent to the Mexico–United States border. It is the eighth-most populous city in the U.S. and second-most populous city in California with a population of over 1.4 million, while the San Diego metropolitan area with over 3.3 million residents is the 18th-largest metropolitan area in the country. San Diego is the county seat of San Diego County.
Known as "America's Finest City", San Diego covers 964 km² with a population of 1.4 million. The city was established in 1769. San Diego is known for San Diego Zoo, Balboa Park, Coronado Beach, among other attractions.
San Diego sits directly on the Mexico-United States border, making it California's southwesternmost major city.
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. 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.
San Diego has a population density of 1,442 people per km² — a relatively spread-out city. San Francisco, with 7,190 people per km², is a densely populated city. San Francisco is dramatically more crowded, with 5.0x the population density.
Size Ratio
San Francisco fits inside San Diego ~7 times
Density Gap
San Francisco is 5.0x more densely populated
San Diego covers 964 km². Cities with a similar urban footprint include Abu Dhabi (972 km²), Dallas (997 km²), Berlin (892 km²), Santiago (838 km²), or Hong Kong (1,114 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 San Diego to San Francisco is 738 km (458 miles), with an estimated flight time of ~1h 22m.
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