# Convert Binary to Decimal in Java

In the previous lesson, we covered the conversion of a Decimal to Binary. Here, you will learn how to convert Binary to Decimal in Java. There are a couple of ways:

• Using the parseInt() method
• With custom logic

## Convert Binary to Decimal in Java using the parseInt() method

We can use the parseInt(String s, int radix) method of Integer class that parses the String argument as a signed integer in the radix specified by the second argument.

### Example

```class Test {

public static void main(String[] args) {

System.out.println(Integer.parseInt("1010", 2));
System.out.println(Integer.parseInt("1001001", 2));
System.out.println(Integer.parseInt("1100010", 2));
}
}```
Output: 10 73 98

## Parse Binary to Decimal with custom logic

We can also write the program without using the pre-defined methods, like in the following example:

```public class Test {

public static void main(String[] args) {

System.out.println(getDecimal(1010));
System.out.println(getDecimal(1001001));
System.out.println(getDecimal(1100010));
}

public static int getDecimal(int binary) {
int decimal = 0;
int n = 0;
while (true) {
if (binary == 0) {
break;
} else {
int temp = binary % 10;
decimal += temp * Math.pow(2, n);
binary = binary / 10;
n++;
}
}

return decimal;
}
}```
Output: 10 73 98

This code defines a static method getDecimal() that converts a binary number passed as an argument to its decimal representation using a while loop.

That’s it.

Happy coding!