Science calculator
Escape Velocity Calculator
Calculate escape velocity from a celestial body.
About the escape velocity calculator
The escape velocity calculator computes the speed needed to escape a celestial body's gravity.
How to use this calculator
- 1
Enter mass
Enter the body's mass in kg.
- 2
Enter radius
Enter the body's radius in meters.
- 3
View results
See the escape velocity.
How the calculation works
v = √(2GM/r). G = 6.674×10⁻¹¹ N·m²/kg².
Example: Earth (5.97×10²⁴kg, 6.37×10⁶m): ≈ 11.2 km/s.
Understanding scientific constants
Key constants used: g = 9.81 m/s² (Earth gravity), c = 299,792,458 m/s (speed of light), G = 6.674×10⁻¹¹ N·m²/kg² (gravitational constant), h = 6.626×10⁻³⁴ J·s (Planck's constant), R = 8.314 J/(mol·K) (ideal gas constant). Results assume ideal conditions — real-world measurements may vary.
Ideal vs. real-world conditions
Most physics calculators assume ideal conditions: no air resistance, perfect vacuums, uniform gravity. Real-world results will differ due to friction, air resistance, temperature variations, and measurement uncertainty. Use these tools for learning and estimation, not precision engineering.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about escape velocity calculator
How accurate is the escape velocity calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.