How to use it
- Enter central-body mass in kilograms.
- Enter orbital radius from the body’s center in meters.
- Calculate ideal circular speed.
Orbital Speed Calculator
Calculate an ideal circular-orbit speed from an entered mass and center-to-center radius.
Important: This calculator is an educational estimate only. It is not aviation, navigation, flight planning, fuel or reserve planning, aircraft or rocket design, certification, launch, propulsion, mission, weapon, maintenance, legal, regulatory, emergency, operational, or safety advice.
About the Orbital Speed Calculator
This calculator applies a simplified two-body circular-orbit equation to entered values.
Formula
v = √(GM ÷ r), using G = 6.67430 × 10⁻¹¹ m³/(kg·s²).
Example
Using an Earth-like mass and a radius of 6,771 km gives an ideal circular speed near 7.67 km/s.
Notes
Perturbations, atmosphere, rotation, trajectory and multiple bodies are excluded. This is not mission or spacecraft-operation guidance.