Decimal to Binary in Java: Explanation & Practice

Problem summary

Write a program that converts a decimal number to its binary representation.

Starter code

public class Main {
    public static void main(String[] args) {
        int decimal = 13; // Test case 1
        
        // Convert to binary
        // Print: Binary: <result>
    }
}

Expected output and test cases

• 13 in binary

  Binary: 1101

• 10 in binary

  Binary: 1010

• 1 in binary

  Binary: 1

Hints

1. Divide by 2 and collect remainders
2. Build binary string from right to left
3. Or use StringBuilder and reverse at end

Related Control Flow exercises

• Practice Star Pyramid in Java
• Practice Digit Frequency in Java
• Practice Sum Until Condition in Java

Practice all Control Flow exercises · Run this idea in the Java compiler