# Convert Int to Binary in Java

Rupam Yadav Jan 30, 2023 Jan 03, 2022

A Binary Number is represented with two binary digits, the `0` and `1`. We can convert an `int` value to a binary value in Java using the three methods listed below.

## Convert Int to Binary Using `Integer.toBinaryString()` in Java

The most common and easiest way to convert an `int` value to binary is to use the `toBinaryString()` function of the `Integer` class. `Integer.toBinaryString()` takes an argument of `int` type.

In the program, we store an `int` value in a variable `numInt` and then pass it as an argument in the `Integer.toBinaryString()` method that returns a `String`.

``````public class JavaExample {
public static void main(String[] args) {
int numInt = 150;
String binaryString = Integer.toBinaryString(numInt);
System.out.println(binaryString);
}
}
``````

Output:

``````10010110
``````

## Convert Int to Binary Using `Integer.toString()` in Java

In this example, we use another method of the `Integer` class method: the `toString()` method.

`Integer.toString()` takes two arguments in which the second argument is optional. The first argument is the value to convert to a `String`, and the second argument is the radix value for conversion.

For our program, we need to use both arguments of the `toString()` function to specify the radix `2`, representing the binary digits `0` and `1`. In simple words, when we use radix `2`, the `int` is converted to a `String` value that represents `0` s and `1` s only.

We print the result that is a binary representation of `numInt`.

``````public class JavaExample {
public static void main(String[] args) {
int numInt = 200;
String binaryString = Integer.toString(numInt, 2);
System.out.println(binaryString);
}
}
``````

Output:

``````11001000
``````

## Convert Int to Binary Using `StringBuilder` and a Loop in Java

The last program takes a traditional approach; instead of using an inbuilt function to convert the `int` value to a binary, we create our function that does the same job.

In the below code, we create a function `convertIntToBinary()` that receives the `int` value as parameter to convert. We set the return type of the function as String.

Inside the `convertIntToBinary()` method, we first check if the `int` variable `numInt` is holding a zero or not. If it is, we return `0` because the binary representation of `0` in `int` is also `0`. If it is a non-zero integer value, we create a `StringBuilder` class and a `while` loop.

We run the loop until `numInt` is greater than zero. In the loop, we perform three steps; the first is to find the remainder of the `numInt` using `numInt % 2` and then append the value of `remainder` to the `StringBuilder`.

For the last step, we divide the `numInt` value with `2` and store it in `numInt` itself. Once we have performed all the steps and are out of the loop, we reverse the `stringBuilder` value to get the correct result and return the result after converting the `stringBuilder` value to a `String`.

In the `main()` method, we take the user’s input and pass it to the `convertIntToBinary()` method that returns the binary result.

``````import java.util.Scanner;

public class JavaExample {
public static void main(String[] args) {
System.out.println("Enter a number to convert it to a binary: ");
Scanner scanner = new Scanner(System.in);
int getIntNum = scanner.nextInt();

String getConvertedResult = convertIntToBinary(getIntNum);
System.out.println("Converted Binary: " + getConvertedResult);

}

static String convertIntToBinary(int numInt) {
if (numInt == 0)
return "0";

StringBuilder stringBuilder = new StringBuilder();

while (numInt > 0) {
int remainder = numInt % 2;
stringBuilder.append(remainder);
numInt /= 2;
}

stringBuilder = stringBuilder.reverse();
return stringBuilder.toString();
}
}
``````

Output:

``````Enter a number to convert it to a binary:
150
Converted Binary: 10010110
``````