Area of a Circle Calculator
Formulas:
Diameter: d = 2 × rd = 2 × 5 = 10
Area: A = π × r²A = π × 5² = 78.5398
Wondering how much pizza you can fit in a circle? This calculator finds the area with just the radius—no need to memorize π, just enter and feast your eyes on the answer!
How to use the area of a circle calculator
To calculate the area of a circle, simply enter the radius of the circle into the calculator. It will automatically compute the area using the formula:
Area = π × radius²
You can use any unit (cm, m, inch, ft), and the result will be displayed in square units.
Example:
- Radius: 7 cm
- Result: 153.94 cm²
What is the area of a circle?
The area of a circle is the space enclosed within its circular boundary. It's a fundamental concept in geometry and used in many real-world applications. The area depends entirely on the radius, which is the distance from the center of the circle to its edge.
The formula uses π (pi ≈ 3.1416), a constant used in circular measurements.
How this calculator helps in daily life
- Geometry homework: Quickly calculate the area of a circle from the radius or diameter
- Crafting & DIY: Measure materials like circular fabric, wood, or floor decals
- Gardening: Calculate the area for circular garden beds or pots
- Construction: Plan round columns, pipes, manholes, or tanks
- Sports: Measure circular fields, tracks, or rings
- Art & design: Scale circular patterns or layouts accurately
This calculator saves time, ensures accuracy, and removes the need for manual calculation.
What units does this calculator support?
You can use any length unit — centimeters, meters, inches, feet — and the output will be in square units (like cm², m², in², ft²).
Is this useful for school or exams?
Definitely. It's perfect for students learning geometry, checking answers, or solving homework problems involving circles.