Created By : Naaz Fatima

Reviewed By : Rajashekhar Valipishetty

Last Updated : May 07, 2023

Use the Schwarzschild Radius Calculator to quickly determine a black hole's Schwarzschild radius and gravitational field. All you have to do is enter the black hole's mass and gravitational field constant values into the calculator's input fields and press the calculate button to get the results in a short amount of time.

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Schwarzschild radius :

What is meant by Schwarzschild Radius?

A black hole is a location in space where the gravitational attraction is so strong that even light cannot escape. The event horizon is a point in space that separates two places with no communication, and the Schwarzchild radius is the distance between two black holes.

A black hole's event horizon separates the locations in space where light can escape the gravitational pull of such huge objects from the points nothing that can resist the black hole's pull. As a result, everything on the event horizon is irrevocably lost. The surface of a black hole is the name given to this phenomenon.

The equation for a black hole is as follows: G = (r x c2)/2m and the gravitational radius of the black hole formula is; r = (2m x G)/c2

  • Where, m = mass of the black hole
  • G = black hole gravity the surface
  • c = speed of the light and c= 299,792,458 m/s
  • r = Schwarzschild radius or event radius or black hole radius

How to find Schwarzschild Radius?

The steps to calculating a black hole's gravitational radius are described below. Follow these guidelines to get the best results in a short amount of time.

  • Step 1: Calculate the mass of the black holes and the gravitational field constant values using the information provided in the question.
  • Step 2: Increase your body mass by a factor of two.
  • Step 3: Multiply it by the gravitational constant.
  • Step 4: To calculate the gravitational radius, divide it by the square of the speed of light.

For more concepts check out to get quick answers by using this free tool.

Schwarzschild Radius Examples

Question 1: Calculate the Schwarzschild radius for a mass of 8.2 x 10^27 grammes on the earth.



Mass of the earth m = 8.2 x 10^27 grams = 8.2 x 10^30 mg

Schwarzschild radius r = (2m x G)/c2

r = (2 x 8.2 x 10^30 x 9.8)/(299,792,458)2

= (160.72 x 10^30)/(8.98 x 1016)

= 1.788 x 10^15

Hence, the Schwarzschild radius is 1.788 x 10^15 mm.

FAQs on Schwarzschild Radius

1. What is the formula for calculating the Schwarzschild radius?

G = rc^2/2m is the Schwarzschild radius formula. The gravitational constant is G, the Schwarzschild radius is r, and the black hole's mass is m.

2. What is the Schwarzschild radius of the Earth?

The Earth's Schwarzschild radius is about one inch, which means you could squeeze the whole mass of the Earth into a sphere the size of a basketball and still not create a black hole: light produced from that mass would be able to escape the gravitational attraction.

3. What is the significance of the Schwarzschild Radius?

It's the distance at which space-time collapses. The tidal forces of the black hole are strongest within this distance.

4. What does the term Schwarzschild mean?

The circular boundary inside which a particular mass (like a star) must collapse to create a black hole. Additionally, the distance between the event horizon and the black hole's centre.

5. What makes a supermassive black hole different from a regular black hole?

Supermassive black holes, as the name implies, have a million to a billion times the mass of a regular star black hole.