Hanoi
3,359 km²
Johannesburg
1,644 km²
Vietnam
South Africa
Area Comparison
Hanoi is 2.0x larger than Johannesburg
Population Comparison
Hanoi has 1.7x more people than Johannesburg
Hanoi is significantly larger, covering 2.0 times the area of Johannesburg. Hanoi spans 3,359 km² (1,297 mi²) while Johannesburg covers 1,644 km² (635 mi²) — a difference of 1,715 km². You could fit Johannesburg inside Hanoi approximately 2 times.
To put Hanoi's size in perspective, its area of 3,359 km² is about 1.2x smaller than Rhode Island. Meanwhile, Johannesburg at 1,644 km² is roughly the same size as London.
Picture Hanoi another way: its area is large enough to fit about 470,000 American football fields, 57 times the area of Manhattan, or 32 times the area of Paris. Johannesburg, by comparison, equals about 230,000 American football fields, 28 times the area of Manhattan, or 16 times the area of Paris.
Hanoi is the capital and second-most populous municipality of Vietnam. It encompasses an area of 3,358.6 km2 (1,296.8 mi2), and as of 2025 has a population of 8,807,523. Hanoi had the second-highest gross regional domestic product of all Vietnamese provinces and municipalities at US$48 billion in 2023, behind Ho Chi Minh City. It hosts 78 foreign embassies, the headquarters of the Vietnam People's Army (VPA), its Vietnam National University system, and other governmental organizations.
Known as "City Between Rivers", Hanoi covers 3,359 km² with a population of 8.1 million. The city was established in 1010. Hanoi is known for Hoan Kiem Lake, Old Quarter, Temple of Literature, among other attractions. The city's main transit system is the Hanoi Metro.
Hanoi encompasses 3,358.6 square kilometers and had a population of nearly 8.8 million as of 2025.
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.
Also known as "Jozi", Johannesburg has an area of 1,644 km² and is home to 4.8 million people. Its history stretches back to 1886. Visitors come for Apartheid Museum, Soweto township, Constitutional Court, and much more.
Johannesburg ranks among the world's 100 largest urban areas, with a metro population of about 6.6 million.
Hanoi has a population density of 2,397 people per km² — a moderately dense city. Johannesburg, with 2,920 people per km², is a moderately dense city. Both cities have comparable density, though Johannesburg is slightly more compact.
Size Ratio
Johannesburg fits inside Hanoi ~2 times
History
Hanoi is ~876 years older
Hanoi covers 3,359 km². Cities with a similar urban footprint include Karachi (3,527 km²), Cairo (3,085 km²), Dubai (4,114 km²), Lima (2,672 km²), or Moscow (2,511 km²).
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).
The straight-line distance from Hanoi to Johannesburg is 9,888 km (6,144 miles), with an estimated flight time of ~12h 8m.
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