The formula to calculate the area of a circle using radius is as follows: Area of a circle = π × r2. And, to calculate the area of a circle using diameter use the following equation: Area of a circle …

See How to Calculate the Area below, but first the calculator: Enter the radius, diameter, circumference or area of a Circle to find the other three.

Oct 25, 2023 · The area of a circle can be calculated using three different formulas. The formulas are used based on whether the radius, diameter, or circumference is known to us.

Aug 26, 2025 · To find the area of a circle, use the formula A = π • r2, where r is the radius of the circle. If you only know the diameter of the circle, then use the formula A = π • (d/2)2 where d …

Aug 1, 2025 · Use this circle calculator to find the area, circumference, radius or diameter of a circle. Given any one variable A, C, r or d of a circle you can calculate the other three unknowns.

Alternatively, the space occupied within the boundary/circumference of a circle is called the area of the circle. The formula for the area of a circle is A = πr 2, where r is the radius of the circle. …

Jun 9, 2025 · Learn how to find the area of a circle with clear formulas, step-by-step examples, and visual explanations—perfect for students and math learners of all levels.