SizerooGuessroo · All sizes

How long is the Danube?

2,850 kmAbout 1,771 miles · Planet-sized

About 2,850 km, through 10 countries.

A red kangaroo would need about 360,000 hops (8 m each) to cover it.

2,850 km
New York to Boston

To scale: the Danube is about 9.3× bigger than New York to Boston.

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Things about the same size

Many real things vary in size, so we use a typical or official figure. Spotted a mistake? Email hello@guessroo.com.