Earth is roughly 12,700 kilometers across, but its exact size depends on how you measure it.

Quick Scoop

Basic size numbers

  • Equatorial diameter (widest part at the equator): about 12,742–12,756 km (≈7,918–7,926 miles).
  • Polar diameter (pole to pole): about 12,714–12,725 km (≈7,907–7,926 miles).
  • Average diameter : often rounded to about 12,742 km.
  • Equatorial circumference (all the way around): about 40,075 km (≈24,901 miles).

These differences happen because Earth isn’t a perfect sphere; it’s an oblate spheroid, slightly squashed at the poles and bulging at the equator.

Other ways to picture Earth’s size

  • Radius : about 6,371 km on average from the center to the surface.
  • Surface area : about 510 million km², with ~71% covered by water and ~29% by land.
  • Volume : about 1.08 trillion cubic kilometers of rock and metal.

Imagine digging a straight tunnel right through the center of Earth at the equator: it would be about 12,756 km long, lined with rock, metal, and intense heat all the way to the core.

Compared to other planets (mini view)

Even though Earth feels huge, in the Solar System it’s mid-sized: larger than Mars and Mercury, a bit bigger than Venus, but tiny compared to giants like Jupiter and Saturn.

[3] [3] [5][3] [3] [3]
Planet Diameter (km)
Mercury 4,879 km
Venus 12,104 km
Earth 12,742 km
Mars 6,779 km
Jupiter 139,820 km

Little “latest” angle

Modern measurements of Earth’s size use satellites, lasers, and GPS, which constantly refine those numbers by tiny amounts as we better understand Earth’s exact shape and how its surface shifts over time.

TL;DR:
Earth’s size is about 12,742 km in diameter, 40,075 km around at the equator, with 510 million km² of surface area—big enough to feel endless, but small on the cosmic map.

Information gathered from public forums or data available on the internet and portrayed here.