Physics

Earth Orbit Calculator

Find orbital speed and period at a given altitude above Earth.

Calculated Output

Orbital speed 7,672.32

Orbital period 92.418

Formula: v = √(GM/r); T = 2π·√(r³/GM)

Step-by-Step Breakdown

1. Values used:

2. Altitude = 400

4. Orbital speed = 7,672.32

5. Orbital period = 92.418

Did this calculator solve your problem today?

The math behind it

Circular orbit speed v = √(GM/r) and period T = 2π√(r³/GM), where r is measured from Earth's center.

400 km (ISS altitude) → about 7672 m/s, 92.6 min period.

Why do higher orbits move slower?

Weaker gravity needs less speed to stay in orbit.