Base conversion in Java

Given a number in a given base, convert it into another target base.


Input : Number = "123"
        Source Base = 8
        Target Base = 10
Output : 83
3 * 1 + 2 * 8 + 1 * 64 = 83

Input : Number = "110"
        Source Base = 2
        Target Base = 10 
Output : 6

The idea is to use toString() method present in Integer wrapper class. We also use partseInt() to parse given string representation of number in a given base.





// Java program to convert one base to other 
public class MainClass {
    public static String baseConversion(String number,
                                 int sBase, int dBase)
        // Parse the number with source radix 
        // and return in specified radix(base)
        return Integer.toString(
            Integer.parseInt(number, sBase),
    public static void main(String[] args)
        String number = "555"; // Number
        int sBase = 8; // Source Base Octal
        int dBase = 10; // Destination Base Decimal
        System.out.println("Octal to Decimal: "
            + baseConversion(number, sBase, dBase));
        dBase = 16; // Destination Base Hexadecimal
        System.out.println("Octal to Hex: "
            + baseConversion(number, sBase, dBase));



Octal to Decimal: 365
Octal to Hex: 16d

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