Circle area calculator
Area of a circle
Area = 2.1² × π = 13.854423602331 meters²
Circle area calculator
The circle area calculator will help you calculate the surface area of a circle. There are multiple circle formulas to find the area of a circle using the radius, diameter or the circumference. With the circle area calculator you can choose which method you want to use.
How do you calculate the area of a circle with the radius?
To calculate the area of your circle, you can multiply the square of a radius by pi and get the area of your circle.
Area = radius² × π
Example: You want to know what the area of a circle with a radius of 1.5 meter is, the formula would look like this: 1.5² × π = 7.07 m2
What is the radius of a circle?
The radius of a circle is from the centre of the circle to the circumference of the circle. In the image below, the red line is called the radius.
How do you calculate the area of a circle with the diameter?
To calculate the area with the diameter of the circle, you can multiply the square of a diameter divided by 2 by pi and get the area of your circle.
Area = (diameter / 2)² × π
Example: You want to know what the area of a circle with a diameter of 1.2 meter is, the formula would look like this: (1.2 / 2)² × π = 1.13 m2
What is the diameter of a circle?
The diameter of a circle is the distance across a circle through the centre. In the image below, the red line indicates the diameter.
How do you calculate the area of a circle with the circumference?
To calculate the area of your circle with the circumference of a circle, you can multiply the square of a circumference by 4 pi and get the area of your circle.
Area = circumference² × 4π
Example: You want to know what the area of a circle with a circumference of 38.5 meter is, the formula would look like this: 38.5² × π = 117.95 m2