Planet size comparison
How big are the planets next to each other? Here are the eight planets, the dwarf planets Pluto and Ceres, and the Sun, each measured across its equator, with Earth as the yardstick. Below them are the largest moons in the Solar System. Every figure comes from NASA's fact sheets, and each name opens its own size page with the source.
The Sun, planets and dwarf planets
The planets and dwarf planets to scale, smallest to largest, with Earth in orange. The Sun is left out of the picture: at this scale it would be 10 times as wide as Jupiter.
| Object | Size | vs Earth |
|---|---|---|
| Ceres (Dwarf planet)The biggest object in the asteroid belt between Mars and Jupiter. | 939.4 km across | 7% of the size |
| Pluto (Dwarf planet)The dwarf planet at the edge of the classical Solar System, with a heart-shaped plain. | 2,376 km across | 19% of the size |
| MercuryThe smallest planet and the closest to the Sun. | 4,879 km across | 38% of the size |
| MarsThe red planet, home of Olympus Mons. | 6,792 km across | 53% of the size |
| VenusEarth's neighbour, wrapped in thick clouds. | 12,104 km across | 95% of the size |
| EarthHome. Measured across the equator. | 12,756 km across | – |
| NeptuneThe farthest planet, an ice giant with supersonic winds. | 49,528 km across | 3.9× bigger |
| UranusAn ice giant that spins on its side. | 51,118 km across | 4× bigger |
| Saturn (Planet only)The ringed giant. Its height here is the planet's own diameter; the rings stick out sideways. | 120,536 km across | 9.4× bigger |
| JupiterThe largest planet, a ball of gas with a storm bigger than Earth. | 142,984 km across | 11× bigger |
| The SunOur star. Measured across its visible surface. | 1,391,400 km across | 110× bigger |
The largest moons
| Object | Size | vs Earth |
|---|---|---|
| Triton (Moon of Neptune)Neptune's largest moon, which orbits backwards. | 2,706.8 km across | 21% of the size |
| Europa (Moon of Jupiter)An icy moon with an ocean hidden under its cracked crust. | 3,121.6 km across | 24% of the size |
| The MoonEarth's only natural satellite. | 3,475 km across | 27% of the size |
| Io (Moon of Jupiter)The most volcanic world in the Solar System. | 3,643 km across | 29% of the size |
| Callisto (Moon of Jupiter)Jupiter's battered outer giant moon, covered in craters. | 4,820.6 km across | 38% of the size |
| Titan (Moon of Saturn)Saturn's giant moon, wrapped in a thick orange haze. Measured at its solid surface. | 5,150 km across | 40% of the size |
| Ganymede (Moon of Jupiter)The largest moon in the Solar System. | 5,262.4 km across | 41% of the size |
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