Earth
Earth is the rocky planet on which we live and the third planet from the Sun.
How big is it?
12,740 km · mean diameter
Mean diameter · approximate
A little perspective
Earth vs Moon: diameter comparison
The mean diameter of Earth is about 3.67 times the mean diameter of the Moon.
Earth is the rocky planet on which we live and the third planet from the Sun.
The Moon is Earth’s natural satellite and the brightest large object in Earth’s night sky.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions.
Measurements, assumptions & sources +
Earth
Mean diameter: 12,740 km; approximate.
Mean-radius spherical model for Earth; actual shape is not perfectly spherical.
NASA JPL — planetary physical parameters
The marked mean diameter is calibrated. Unmeasured illustration details are representative.
Moon
Mean diameter: 3,475 km; approximate.
Rounded mean-radius model of Moon. The derived area and volume describe a sphere; surface terrain and flattening are omitted.
NASA JPL — Planetary satellite physical parameters
The marked mean diameter is calibrated. Unmeasured illustration details are representative.
Use the visual comparison to explore its scale, then check the measurements and sources.
Change your perspective
Put it next to…
Choose a suggestion to redraw the comparison, or open its page to learn what it is.
Why this measurement?
Why we use 12,740 km
We compare the mean diameter of Earth. This is an estimate; check the notes for its rounding and uncertainty.
Mean-radius spherical model for Earth; actual shape is not perfectly spherical.
The marked horizontal span follows the measured feature, not the edges of the image. How calibrated comparisons work →
Recorded properties
Dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 12,740 km | Not recorded | approximate | |
| 6,371 km | Not recorded | approximate | |
| 40,030 km | Not recorded | derived | |
| 510,100,000 km² | Not recorded | derived | |
| 1.083 × 10¹² km³ | Not recorded | derived | |
| 1 M⊕ | Not recorded | approximate | |
| 9.807 m/s² | Not recorded | approximate | |
| 1 AU | Not recorded | rounded orbital anchor | |
| 107,200 km/h | Not recorded | rounded orbital anchor | |
| 384,400 km | Not recorded | approximate | |
| 4.54 Gyr | Not recorded | rounded geological anchor |
Around this scale
Explore nearby values.
Compare examples with lower, similar and higher values. Each card names the measurement being compared.
Nearest lower valuePlanets, moons and spaceVenus12,100 kmMean diameterVenus is a rocky planet orbiting the Sun, covered by thick clouds of carbon dioxide and sulphuric acid.
Around the same scalePlanets, moons and spaceWhite dwarf12,000 kmDiameterA white dwarf is the dense, hot remnant core left behind after a star like the Sun has exhausted its nuclear fuel and shed its outer layers.
Nearest higher valuePlanets, moons and spaceNeptune49,240 kmMean diameterNeptune is an ice giant planet with a deep blue atmosphere, orbiting the Sun beyond Uranus.Sources and method
Want to check the number?
The source records and measurement method remain available for inspection.
- NASA JPL — planetary physical parametersMean radii and masses. Spherical area and volume here are derived from mean radius. This atlas rounds for scale comparison.
- NASA — Planet CompareConventional surface gravities; giant-planet values refer to an atmospheric reference level. Earth uses standard gravity, 9.80665 m/s².
- Defined examples — our methodology
- NASA — Earth and Moon by the numbersMean radius and average orbital distance; rounded values.
More ways to see it
Curated comparisons
There’s always another scale
Follow your curiosity.
SpaceMoon3,475 kmThe Moon is Earth’s natural satellite and the brightest large object in Earth’s night sky.
SpaceJupiter139,800 kmJupiter is a giant planet composed mainly of hydrogen and helium, orbiting the Sun beyond the asteroid belt.
SpaceSun1,391,000 kmThe Sun is the star at the centre of the Solar System.SpaceVenus12,100 kmVenus is a rocky planet orbiting the Sun, covered by thick clouds of carbon dioxide and sulphuric acid.SpaceWhite dwarf12,000 kmA white dwarf is the dense, hot remnant core left behind after a star like the Sun has exhausted its nuclear fuel and shed its outer layers.
SpaceMars6,779 kmMars is a rocky planet orbiting the Sun, with a reddish surface due to iron oxide.
SpaceGanymede5,262 kmGanymede is a natural satellite of Jupiter and contains a magnetic field generated by its partially liquid core.
SpaceTitan5,150 kmTitan is a natural satellite of Saturn, with a thick nitrogen-rich atmosphere and surface lakes of hydrocarbons.A closer look