Earth vs Mercury: size comparison
Earth: 12,742 km. Mercury: 4,879 km. Both silhouettes are drawn at the same scale.
Size ratio: ×2.6
Earth
12,742 km
What is measured Mean diameter of the Earth
Earth's equator is about 40,075 km around.
Source : Wikipedia — Earth
Mercury
4,879 km
What is measured Diameter of Mercury
Mercury is barely larger than the Moon.
Source : Wikipedia — Mercury (planet)