Java float keyword

The Java float keyword is a primitive data type. It is a single-precision 32-bit IEEE 754 floating point. It is used to declare the variables and methods. It represents the fractional numbers.

Points to remember

The float covers a range from 1.40129846432481707e-45 to 3.40282346638528860e+38 (positive or negative).
Its default value is 0.0f.
Its default size is 4 byte.
It can be used to save memory in large arrays of floating point numbers.
It is not a good approach to use float for precise values, such as currency.

Examples of Java float keyword

Example 1

Let's see a simple example to display float type variable.

public class FloatExample1 {

	public static void main(String[] args) {
		
		float num1=5.5f;
		float num2=5f;
		System.out.println("num1: "+num1);
		System.out.println("num2: "+num2);
	}	
}

Output:

num1: 5.5
num2: 5.0

Example 2

In this example, we provide integer value to float variable. Here, compiler implicitly typecast integer to float and display the corresponding value in fractional form.

public class FloatExample2 {

	public static void main(String[] args) {

		float num1=5;
		float num2=10;
		System.out.println("num1: "+num1);
		System.out.println("num2: "+num2);
	}
}

Output:

num1: 5.0
num2: 10.0

Example 3

In this example, we provide bigger decimal value.

public class FloatExample3 {

	public static void main(String[] args) {

		float num1=581216732.323433f;
		float num2=7.83684987683688f;
		System.out.println("num1: "+num1);
		System.out.println("num2: "+num2);

	}
	
}

Output:

num1: 5.812167E8
num2: 7.8368497

Example 4

In this example, we provide float value to the decimal variable.

public class FloatExample4 {

	public static void main(String[] args) {
		
            float num=56.34;
		System.out.println("num1: "+num);			
	}
	
}

Output:

Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
	Type mismatch: cannot convert from double to float

Example 5

In this example, we provide the end range of decimal value.

public class FloatExample5 {

	public static void main(String[] args) {

		float num1=1.40129846432481707e-45f;
		float num2=3.40282346638528860e+38f;
		System.out.println("num1: "+num1);
		System.out.println("num2: "+num2);	}
}

Output:

num1: 1.4E-45
num2: 3.4028235E38

Example 6

In this example, we provide the value in scientific notation

public class FloatExample6 {

	public static void main(String[] args) {

		float num1=1873.2f;
		//providing same value in scientific notation
		float num2=1.8732e3f;
		System.out.println("num1: "+num1);
		System.out.println("num2: "+num2);
	}
	
}

Output:

num1: 1873.2
num2: 1873.2

Example 7

In this example, we create a method returning float value.

public class FloatExample7 {

	public float display(float weight)
	{
		return weight;
	}
	
	public static void main(String[] args) {
		
		FloatExample7 d=new FloatExample7();
		System.out.println(d.display(62.5f));
	}	
}

Output: