Orbital Mechanics Calculator

Calculate gravitational acceleration, escape velocity, orbital velocity, and orbital period using Kepler's third law. Includes presets for all planets — free online tool

g = GM/r²

v_escape = √(2GM/r)

v_orbital = √(GM/r)

T² = (4π²/GM)a³ (Kepler's 3rd law)

G = 6.67430e-11 m³/(kg·s²)

Presets

Input Parameters

Body mass M (kg)

Body radius R (m)

Orbit altitude (m)

Semi-major axis a (m)

Results

Surface gravity g

9.8200 m/s²

Escape velocity

11185.98 m/s

= 11.19 km/s

Orbital velocity

7672.49 m/s

= 7.67 km/s

Orbital period T

5544.93 s

= 1.54 h = 0.0642 d