Planets · #23 biggest of 1,014
How big is Neptune?
49,244 km
Neptune measures 49,244 km. That's about 3.86 Earths lined up end to end.
By the numbers
- That's 49,244 km, or about 30,599 miles.
- It's about 29 million times taller than an average adult (1.7 m).
- Roughly 3.86 Earths could line up across it.
- Walking nonstop, you'd need about 407 days to travel its length.
- Out of all 1,014 things in this collection, it ranks #23 by size.
Size comparison
How Neptune stacks up against things of a similar size. Tap any bar to explore it.
red dwarf star
200,000 km
Jupiter
139,822 km
Saturn
116,464 km
Uranus
50,724 km
Neptune
49,244 km
Great Wall of China
21,196 km
white dwarf star
14,000 km
Earth
12,742 km
Venus
12,104 km
Bars use a logarithmic scale so everything fits — real differences are even more extreme!
Fun fact
Standing beside it, an average person (1.7 m tall) would reach only about less than 0.001% of its height.
More in Planets
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