It’s been said that Venus is Earth’s twin planet, in terms of size and composition. So when you ask how big is Venus, you know it’s going to be pretty close to Earth. Of course, Venus has incredibly high temperatures, crushing pressure and a poisonous atmosphere, so it’s not exactly a twin of Earth.
Let’s start with the size of Venus. The diameter of Venus is 12,100 km. That’s about 95% of the diameter of Earth. If you put Earth and Venus side by side, it would be pretty hard to see which one was larger.
The volume of Venus is 9.38 x 1011 km3, written out, that’s 938,000,000,000 cubic kilometers. Of course, since Venus isn’t as big as Earth, it actually has a smaller volume. Venus has only 86% the volume of Earth. In other words, you could fit 1.16 Venuses inside Earth.
The surface area of Venus is 4.6 x 108 km2. That works out to be 460,000,000 square kilometers. Again, that’s a little smaller than Earth. The surface area of Venus is only 90% the surface area of Earth.
We have written many articles about Venus for Universe Today. Here’s an article about Venus’ wet, volcanic past, and here’s an article about how Venus might have had continents and oceans in the ancient past.
We have recorded a whole episode of Astronomy Cast that’s only about planet Venus. Listen to it here, Episode 50: Venus.