Orbital Speed Calculator

Use this orbital speed calculator to estimate the speed needed for an object to stay in a circular orbit around a planet, moon, or custom body.

Orbital speed depends on the central body’s mass and the distance from its center. Lower orbits usually require faster speeds than higher orbits.

Select Planet or Moon

Body Name

Body Mass (×10²⁴ kg)

Body Radius (km)

Orbit Altitude Above Surface (km)

Orbital Speed Result

Orbital Speed -

Speed in km/h -

Orbit Radius -

Estimated Orbital Period -

Status: -

Understanding Orbital Speed

Orbital speed is the speed an object needs to keep moving around a planet, moon, or star without falling directly back to the surface. Satellites, space stations, moons, and planets all stay in orbit because their forward motion balances gravity.

A low orbit usually requires a faster speed than a high orbit. This happens because gravity is stronger closer to the central body.

The International Space Station orbits Earth at roughly 7.7 km/s, which is about 28,000 km/h.

How Orbital Speed Is Calculated

Orbital speed depends on the mass of the central body and the distance from its center. The farther an object is from the planet or moon, the slower its circular orbital speed becomes.

This calculator uses a simplified circular orbit formula and does not include atmospheric drag, elliptical orbit effects, or spacecraft propulsion.

Orbital Speed vs Escape Velocity

Concept	Meaning
Orbital Speed	The speed needed to stay in orbit around a body.
Escape Velocity	The speed needed to leave a body’s gravity without falling back.
Low Orbit	Usually faster because the object is closer to the planet.
High Orbit	Usually slower because gravity is weaker farther away.

Why Orbital Speed Matters

Orbital speed is essential for satellite launches, space station missions, GPS systems, weather satellites, and planetary exploration. If a spacecraft moves too slowly, it falls back. If it moves too fast, it may escape or enter a different orbit.

Engineers carefully calculate orbital speed before placing satellites into low Earth orbit, geostationary orbit, lunar orbit, or interplanetary transfer paths.