Philadelphia
370 km²
Rio de Janeiro
1,221 km²
United States
Brazil
Area Comparison
Philadelphia is 3.3x smaller than Rio de Janeiro
Population Comparison
Philadelphia has 4.2x fewer people than Rio de Janeiro
In terms of area, Rio de Janeiro is 3.3x the size of Philadelphia. Rio de Janeiro spans 1,221 km² (471 mi²) while Philadelphia covers 370 km² (143 mi²) — a difference of 851 km². You could fit Philadelphia inside Rio de Janeiro approximately 3 times.
To put Philadelphia's size in perspective, its area of 370 km² is about 1.6x smaller than Seoul. Meanwhile, Rio de Janeiro at 1,221 km² is about 1.3x smaller than London.
In more relatable units, Philadelphia's 370 km² is about 52,000 American football fields, 180 times the area of Monaco, or 110 times the area of Central Park. For Rio de Janeiro, that's about 171,000 American football fields, 21 times the area of Manhattan, or 12 times the area of Paris.
Philadelphia, colloquially referred to as Philly, is the most populous city in the U.S. state of Pennsylvania, and the sixth-most populous city in the United States, with a Census-estimated population of 1,574,281 in July 2025. The Philadelphia metropolitan area has 6.33 million residents and is the nation's ninth-largest metropolitan area. Philadelphia is known for its culture, cuisine, and history, maintaining contemporary influence in business and technology, sports, and music.
Known as "Philly", Philadelphia covers 370 km² with a population of 1.6 million. The city was established in 1682. Philadelphia is known for Liberty Bell, Independence Hall, Philly Cheesesteak, among other attractions.
Philadelphia is the sixth-most populous US city, with an estimated 1,574,281 residents as of July 2025.
Rio de Janeiro, also known simply as Rio, is the capital of the state of Rio de Janeiro. It is the second-most-populous city in Brazil after São Paulo and the sixth-most-populous city in the Americas.
Often called "Cidade Maravilhosa", Rio de Janeiro has an area of 1,221 km² and is home to 6.8 million people. It was established in 1565. Visitors come for Christ the Redeemer, Sugarloaf Mountain, Copacabana beach, and much more. Getting around is easy with the MetrôRio.
Rio de Janeiro is the second-most-populous city in Brazil after São Paulo and the sixth-most-populous in the Americas.
Philadelphia has a population density of 4,324 people per km² — a moderately dense city. Rio de Janeiro, with 5,528 people per km², is a densely populated city. Both cities have comparable density, though Rio de Janeiro is slightly more compact.
Size Ratio
Philadelphia fits inside Rio de Janeiro ~3 times
History
Rio de Janeiro is ~117 years older
Philadelphia covers 370 km². Cities with a similar urban footprint include Seattle (369 km²), Dhaka (368 km²), Portland (376 km²), Atlanta (348 km²), or Denver (401 km²).
Rio de Janeiro covers 1,221 km². Cities with a similar urban footprint include San Antonio (1,209 km²), Lagos (1,172 km²), Rome (1,285 km²), Los Angeles (1,302 km²), or Hong Kong (1,114 km²).
The straight-line distance from Philadelphia to Rio de Janeiro is 7,737 km (4,807 miles), with an estimated flight time of ~9h 36m.
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