By The Numbers Earth's Size Volume: 6.73 x 1011 cubic miles (1.083 x 1012 km3) Radius: 3,959 miles (6,371 km) Diameter: 7,918 miles (12,742 km) Surface Area: 1.97 x108 square miles (5.1 x 108 km2) Mass: 5.972 x 1024 kg