Area of Circle Calculator
Calculate the area of a circle using radius, diameter, or circumference.
Calculate From
Circle Diagram
Area = pi x r^2
Step-by-Step Solution
Step 1: Identify the radius
r = 5.0000
Step 2: Apply the formula A = pi x r^2
A = pi x (5.0000)^2
Step 3: Calculate
A = pi x 25.0000 = 78.5398
Area of Circle
78.5398
square units
rRadius
5.0000
dDiameter
10.0000
CCircumference
31.4159
AArea
78.5398
Quick Reference
| Radius | Area |
|---|---|
| 1 | 3.1416 |
| 2 | 12.5664 |
| 3 | 28.2743 |
| 4 | 50.2655 |
| 5 | 78.5398 |
| 10 | 314.1593 |
Circle Area Formulas
From Radius
A = pi x r^2
From Diameter
A = pi x (d/2)^2 = pi x d^2/4
From Circumference
A = C^2 / (4 x pi)