Schwarzschild Radius Calculator
Calculate the event horizon radius of a black hole
About this calculator
The Schwarzschild Radius Calculator determines the event horizon radius of a black hole based on its mass. This critical boundary represents the point of no return where nothing, not even light, can escape the black hole's gravitational pull. This calculator is essential for astrophysicists, astronomy students, and space enthusiasts studying black hole physics and understanding how mass relates to the size of these cosmic phenomena. It provides instant calculations using Einstein's general relativity equations.
How to use
Enter the mass of the black hole in kilograms, solar masses, or other available units. The calculator will automatically compute the Schwarzschild radius using the formula Rs = 2GM/c², where G is the gravitational constant, M is mass, and c is the speed of light. Results show the event horizon radius in meters or kilometers.
Frequently asked questions
What is the Schwarzschild radius?
The Schwarzschild radius is the critical distance from a black hole's center where the escape velocity equals the speed of light, forming the event horizon boundary.
How does mass affect the Schwarzschild radius?
The Schwarzschild radius is directly proportional to mass - more massive black holes have larger event horizons and greater Schwarzschild radii.
Can objects smaller than their Schwarzschild radius exist?
If any object is compressed to within its Schwarzschild radius, it becomes a black hole. Normal matter cannot exist stably below this critical size.