Circle Measurements Calculator
Calculate radius, diameter, circumference, and area of a circle from any given measurement
Calculate Circle Measurements
Select the measurement you know
Enter a positive value to calculate other measurements
Circle Measurement Results
Example Calculation
Garden Circle Example
Problem: A circular garden has a radius of 5 meters.
Find: Diameter, circumference, and area of the garden.
Solution
Given: Radius (r) = 5 m
Diameter: d = 2r = 2 × 5 = 10 m
Circumference: c = 2πr = 2 × π × 5 ≈ 31.416 m
Area: A = πr² = π × 5² ≈ 78.540 m²
Circle Formulas
From Radius (r)
From Diameter (d)
From Circumference (c)
From Area (A)
Circle Facts
π (Pi) is approximately 3.14159265359
A circle has 360 degrees or 2π radians
The ratio of circumference to diameter is always π
Circles have the largest area for a given perimeter
All points on a circle are equidistant from the center
Understanding Circle Measurements
What are Circle Measurements?
Circle measurements are the fundamental properties that define a circle: radius, diameter, circumference, and area. These measurements are interconnected, meaning if you know one, you can calculate all the others using mathematical formulas.
Key Definitions
- •Radius: Distance from center to edge
- •Diameter: Distance across circle through center
- •Circumference: Distance around the circle
- •Area: Space inside the circle
Real-World Applications
- •Architecture and construction planning
- •Garden and landscape design
- •Manufacturing and engineering
- •Sports field and track design
- •Material calculation and cost estimation
Fun Fact: The value of π was first calculated by ancient mathematicians like Archimedes around 250 BC using geometric methods!