It is difficult to define the biggest cities in the world for a few reasons.

Do you define a city based on population, geographic area, or a combination of the two?

Should you include the other municipalities or suburbs of the city?

10 Biggest Cities in the World

From left to right: Dhaka, Bangladesh; Tokyo, Japan; Osaka, Japan; Shanghai, China; Cairo, Egypt; Delhi, India; Beijing, China; and Mexico City, Mexico

What happens if different areas have differing opinions on what constitutes a city in the first place?

Read on to see which cities made the list!

The Largest Cities in the World (Based on Population)

1.

Tokyo, Japan - 10 Biggest Cities in the World

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In fact, Tokyo has a population so large, it almost beats the entirety of Canada!

Still, the city may not stay at the top of this list for long.

Delhi has been recognized as an important city center for much of its history since the 6th century BCE.

Delhi, India - 10 Biggest Cities in the World

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It is also the largest city proper in all of the Western Hemisphere and Southern Hemisphere.

Remnants of both histories are clear long after independence.

It is the economic and cultural center of the country and another historically populated city.

Shanghai, China - 10 Biggest Cities in the World

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It was also a major center for trade and commerce during the medieval period.

Today, the city preserves architecture from its colonial and earlier history.

Much of its history was influenced by colonial rule from Portugal and Britain.

Sao Paulo, Brazil - 10 Biggest Cities in the World

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Mumbai later became a critical center for the fight for Indian independence.

Today, Mumbai is a commercial center of the world and home to Bollywood and other cultural industries.

It is also considered an important center for Japanese culture, finance, and research.

Mexico City, Mexico - 10 Biggest Cities in the World

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Dhaka, Bangladesh - 10 Biggest Cities in the World

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Cairo, Egypt - 10 Biggest Cities in the World

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Mumbai, India - 10 Biggest Cities in the World

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Beijing, China - 10 Biggest Cities in the World

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Osaka, Japan - 10 Biggest Cities in the World

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