Area of a Circle Calculator

Find the area of a circle with radius, diameter and circumference


A circle is a simple shape that is the set of all points that are a fixed distance from a given point. A circle can be drawn with a compass or pen, or it can be described algebraically. The distance from a fixed point in a plane to a given point is called a radius. A circle is a special type of a sphere. The fixed point is called the center of the circle. The distance from a point on a circle to the center is called the radius of the circle. The distance from a point on a circle to a line that is not part of the circle is called the diameter of the circle. A circle with a radius of one is called a unit circle. It is a convenient way of representing a circle in Euclidean geometry. Any circle that is not a unit circle is called a non-unit circle.

area of a circle

Area of a Circle

The area of a circle is defined as the amount of space it takes to completely surround the circle. It is calculated by the equation A = πr2, where A is the area, r is the radius, and π is the constant pi (approximately 3.14159). The formula can be rearranged to find the radius of a circle if you know its area. Area of a circle = π times the square of the radius.

area of a circle calculator

Area of Circle formula

Given the radius of the circle, the area is the radius squared times pi. Given pi is 3.14159, it would be written as: area=r2*pi

◉ Area of a circle with radius.

Area of circle = π(r)² = π(radius)²

◉ Area of a circle calculator with diameter

Area of circle = π(D/2)² = π(dimater/2)²

◉ Area of a circle with circumference

Area of circle = C²/4π = circumference²/4π

Real example of used area of circle

◉ When calculating the area of a circle, the formula is pi x radius squared. Yes, pi is a complicated number. The truth is, though, that if you want to find the area of a circle you will need to know pi. When you're calculating the area of a pizza, for example, you will need to figure the diameter of the pizza, and then multiply that by pi. The same is true for the area of a cake or any other round object. To determine the area of a circular object, you will need to measure the diameter of the circle. Once you have the diameter, you will need to use the formula for the area of a circle. The formula is pi x diameter squared.

How to use area of a circle calculator❓

◉ Given a radius of a circle, the formula for finding its area is A = πr2. It is a powerful tool for calculating how much area a circle takes up. For example, a circle with a radius of 10 meters can be found by entering 10 for the radius value. By doing so, the area is calculated to be 314.16 square meters. If you don't know the radius of a circle, there is a formula for that as well. If you know the diameter of the circle, just divide diameter by two to obtain the radius. The formula for area of circle with diameter d is A = πd2/4 When using the above formula.

How to solve area of circle ❓

Example.1:-The radius of a circle is 10 cm, find its area?

Answer:- Area = πr² = 22/7 * (10)² = 314.15 cm².

Example.2:-The circumference of a circle is 20 cm, find it's area ?

Answer:- Circumference of circle = 2πr = 20 cm

radius = 10/π

Area = πr² = π * (10/ π)² = 100/π = 31.83 cm².

Example.3:-The diameter of a circle is 20cm, find it's area?

Answer:- diameter = radius/2 ⇨ radius = diameter/2 = 20/2 = 10 cm.

Area = πr² = π * (10)² = 314.15 cm².

Example.4:-Area of 12 inch radius of a circle,

Answer:- Area of a circle = π(radius)² = 22/7 * (12)² = 452.38934 inch².