Convert Earth's Equatorial Radius (R⊕) to Foot (ft) instantly.
About these units
Earth's Equatorial Radius (R⊕)
The Earth's equatorial radius is approximately 6,378.1 km. This distance represents the radius measured along the equator, where Earth's rotational bulge makes it slightly larger than the polar radius. Geodesists, cartographers, and astronomers use the equatorial radius for mapping, satellite positioning, and calculating gravitational effects. It is fundamental to defining the shape of the Earth as an oblate spheroid rather than a perfect sphere. Precise knowledge of R⊕ enables accurate navigation, climate modeling, and orbital calculations, forming the basis for modern geodesy and Earth observation systems.
Foot (ft)
A foot, equal to 12 inches, has been used for thousands of years and likely originated from the length of a human foot. Though early definitions varied, the modern standard foot—established internationally in 1959—provides a stable and consistent reference. The foot remains the foundation of architectural and construction measurements in the United States, influencing everything from lumber dimensions to ceiling heights and room layouts. Because the foot is intuitively relatable to human scale, people often estimate heights, furniture sizes, and walking distances in feet. In aviation, altitude is universally measured in feet worldwide, even in countries that otherwise use metric units—an unusual but deeply embedded global convention. The foot's persistence shows how cultural inertia can remain strong even when a unit predates modern scientific measurement.