Physics

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Orbital Velocity Calculator.

Calculate circular orbital velocity around a central mass.

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Set your values

Results update as you type.

02 / ANSWER

Central mass

Orbital radius

Orbital velocity

0.000000m/s

Specific orbital energy

0.000000J/kg

Results update automatically as you type.

Use Cases

Satellite Orbit Planning

Determine the required speed for a satellite to maintain a circular orbit at a given altitude around Earth or another planet.

Example: For Earth (mass 5.972e24 kg) at radius 7,000 km, velocity ≈ 7.5 km/s.

Astronomy Education

Help students understand how mass and distance affect orbital speeds in the solar system or binary star systems.

Example: Calculate the orbital speed of the Moon around Earth using its average distance.

Frequently Asked Questions

What is orbital velocity?: Orbital velocity is the speed needed for an object to stay in a stable circular orbit around a central mass, balancing gravitational pull and inertia.
How is orbital velocity calculated?: It is calculated using the formula v = sqrt(G * M / r), where G is the gravitational constant, M is the central mass, and r is the orbital radius.
Does this calculator work for any central mass?: Yes, you can input any central mass in kilograms, from small bodies to stars, as long as you provide the orbital radius in meters.

Tips & Common Mistakes

Tips

Ensure the orbital radius is measured from the center of the central mass, not from its surface.
Use consistent units: mass in kilograms and radius in meters for accurate results.
Remember that this calculator assumes a circular orbit; elliptical orbits have varying speeds.
For quick estimates, you can use Earth's mass as 5.972 × 10^24 kg.

Common Mistakes to Avoid

Using the planet's radius instead of the orbital radius (distance from center).
Forgetting to convert units, such as using kilometers for radius without converting to meters.
Assuming the result is in km/s when the calculator outputs in m/s (check the output unit).

Last updated: August 13, 2026

Use Cases

Satellite Orbit Planning

Determine the required speed for a satellite to maintain a circular orbit at a given altitude around Earth or another planet.

Example: For Earth (mass 5.972e24 kg) at radius 7,000 km, velocity ≈ 7.5 km/s.

Astronomy Education

Help students understand how mass and distance affect orbital speeds in the solar system or binary star systems.

Example: Calculate the orbital speed of the Moon around Earth using its average distance.

Frequently Asked Questions

What is orbital velocity?

Orbital velocity is the speed needed for an object to stay in a stable circular orbit around a central mass, balancing gravitational pull and inertia.

How is orbital velocity calculated?

It is calculated using the formula v = sqrt(G * M / r), where G is the gravitational constant, M is the central mass, and r is the orbital radius.

Does this calculator work for any central mass?

Yes, you can input any central mass in kilograms, from small bodies to stars, as long as you provide the orbital radius in meters.

Tips & Common Mistakes

Tips

Ensure the orbital radius is measured from the center of the central mass, not from its surface.
Use consistent units: mass in kilograms and radius in meters for accurate results.
Remember that this calculator assumes a circular orbit; elliptical orbits have varying speeds.
For quick estimates, you can use Earth's mass as 5.972 × 10^24 kg.

Common Mistakes to Avoid

Using the planet's radius instead of the orbital radius (distance from center).
Forgetting to convert units, such as using kilometers for radius without converting to meters.
Assuming the result is in km/s when the calculator outputs in m/s (check the output unit).

Use Cases

Satellite Orbit Planning

Determine the required speed for a satellite to maintain a circular orbit at a given altitude around Earth or another planet.

Example: For Earth (mass 5.972e24 kg) at radius 7,000 km, velocity ≈ 7.5 km/s.

Astronomy Education

Help students understand how mass and distance affect orbital speeds in the solar system or binary star systems.

Example: Calculate the orbital speed of the Moon around Earth using its average distance.

Frequently Asked Questions

What is orbital velocity?

Orbital velocity is the speed needed for an object to stay in a stable circular orbit around a central mass, balancing gravitational pull and inertia.

How is orbital velocity calculated?

It is calculated using the formula v = sqrt(G * M / r), where G is the gravitational constant, M is the central mass, and r is the orbital radius.

Does this calculator work for any central mass?

Yes, you can input any central mass in kilograms, from small bodies to stars, as long as you provide the orbital radius in meters.

Tips & Common Mistakes

Tips

Ensure the orbital radius is measured from the center of the central mass, not from its surface.
Use consistent units: mass in kilograms and radius in meters for accurate results.
Remember that this calculator assumes a circular orbit; elliptical orbits have varying speeds.
For quick estimates, you can use Earth's mass as 5.972 × 10^24 kg.

Common Mistakes to Avoid

Using the planet's radius instead of the orbital radius (distance from center).
Forgetting to convert units, such as using kilometers for radius without converting to meters.
Assuming the result is in km/s when the calculator outputs in m/s (check the output unit).