Calculating the Area of Different Shapes in Golang

In this blog post, we will explore a Golang program that calculates the area of three common shapes: circle, rectangle, and triangle. We will provide a step-by-step explanation of each calculation to ensure a clear understanding of the implementation.

The "Area Calculator" Golang Program

package main

import (

// calculateCircleArea calculates the area of a circle given its radius.
func calculateCircleArea(radius float64) float64 {
	return math.Pi * math.Pow(radius, 2)

// calculateRectangleArea calculates the area of a rectangle given its length and width.
func calculateRectangleArea(length, width float64) float64 {
	return length * width

// calculateTriangleArea calculates the area of a triangle given its base and height.
func calculateTriangleArea(base, height float64) float64 {
	return 0.5 * base * height

func main() {
	// Example usage
	circleRadius := 5.0
	rectangleLength := 4.0
	rectangleWidth := 6.0
	triangleBase := 8.0
	triangleHeight := 3.0

	// Calculate areas of different shapes
	circleArea := calculateCircleArea(circleRadius)
	rectangleArea := calculateRectangleArea(rectangleLength, rectangleWidth)
	triangleArea := calculateTriangleArea(triangleBase, triangleHeight)

	// Print the calculated areas
	fmt.Printf("Circle Area: %.2f\n", circleArea)
	fmt.Printf("Rectangle Area: %.2f\n", rectangleArea)
	fmt.Printf("Triangle Area: %.2f\n", triangleArea)
Circle Area: 78.54
Rectangle Area: 24.00
Triangle Area: 12.00

Code Explanation

We start by defining three functions: calculateCircleArea, calculateRectangleArea, and calculateTriangleArea. Each function calculates the area of a specific shape (circle, rectangle, and triangle) based on its given parameters.

calculateCircleArea takes the radius of the circle as input and returns the area. It uses the formula: Area = π * radius^2, where radius is the radius of the circle and π (Pi) is a constant provided by the math package.

calculateRectangleArea takes the length and width of the rectangle as inputs and returns the area. It uses the formula: Area = length * width.

calculateTriangleArea takes the base and height of the triangle as inputs and returns the area. It uses the formula: Area = 0.5 * base * height.

In the main function, we provide example values for the radius of the circle, the length and width of the rectangle, and the base and height of the triangle.

We then call each area calculation function with the respective parameters and store the results in variables: circleArea, rectangleArea, and triangleArea.

Finally, we use fmt.Printf to print the calculated areas with two decimal places for precision.


In this blog post, we explored how to calculate the area of different shapes in Golang. By utilizing the corresponding area formulas for circles, rectangles, and triangles, we efficiently perform the required computations. Golang's built-in mathematical functions and straightforward syntax make it an ideal choice for handling various geometric calculations.

As you continue to delve into Golang's capabilities, understanding how to compute areas and other mathematical properties of shapes will significantly enhance your ability to solve complex problems in your programming projects. Happy coding!