Java Calculator Project

Build a simple calculator in Java using methods, user input, and arithmetic operators.

Tutorials › Java Projects › Java Calculator Project

Project Overview

Build a simple calculator in Java using methods, user input, and arithmetic operators.

This beginner Java project helps you practice real coding skills with a small program you can run, edit, and improve.

Java Code

import java.util.Scanner;

public class Calculator {
  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.print("Enter first number: ");
    double a = input.nextDouble();
    System.out.print("Enter second number: ");
    double b = input.nextDouble();
    System.out.println("Sum: " + (a + b));
    System.out.println("Difference: " + (a - b));
    input.close();
  }
}

How to Run This Project

  1. Install the Java JDK.
  2. Create a new file. Use the public class name as the file name.
  3. Paste the code into the file.
  4. Compile it using javac FileName.java.
  5. Run it using java FileName.

What You Practice

  • Java syntax
  • Variables and data types
  • Conditions and loops
  • Methods, classes, or objects depending on the project
  • Problem solving

Project Improvements

  • Add input validation.
  • Add better menus and messages.
  • Use classes and objects for better structure.
  • Save data to a file.
  • Convert the project into a GUI app later.

Related Java Lessons

Java Tutorial | Methods | Classes | Objects | Collections