Calculate the Schwarzschild Radius of a Black Hole

Calculator for the radius of a black hole's event horizon from its mass. Every mass has a Schwarzschild radius to which it would have to shrink to become a black hole. The event horizon is the limit beyond which nothing can escape the black hole's gravitational force, including light, which is why it is black.

The Schwarzschild radius is calculated as rs = 2GM/c² with the gravitational constant G, the object mass M and the speed of light c.
In practice, this formula is often used for the radius in meters and the mass in kilograms, which also this calculator uses: rs = M * 1.485 * 10-27 m / kg

Mass M:
Schwarzschild radius rs:

Round to    decimal places.

Examples: the earth as a black hole would have a radius of almost 9 millimeters, the sun almost 3 kilometers. A human would have a radius of about a tenth of a yoctometer (∼ 0.1 * 10-24 m).

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