Java

How to Round Up in Java

Round-off means a number is converted to the closest suitable place value. There are two types of round-off: “round up” and “round down”. In a round-up, the number is rounded up to the closest number. While in the round down, it is rounded according to the nearest number. It is mostly used to make long, complex numbers easier for better understanding and calculation.

This article will demonstrate how to round up in Java.

How to Round Up in Java?

In Java, there are two methods that can be utilized to round up the values:

  • Math.ceil()
  • Math.round()

Let’s use both of them one by one!

How to Round Up in Java Using Math.ceil() Method?

ceil” is derived from the word “ceiling”. The “ceil()” method belongs to the Java “Math” class and rounds up the number towards its closest integer. It outputs the “double” type, a decimal value greater than or equal to the parameter.

Syntax

The syntax of the Math.ceil() method is:
Math.ceil(number)

Here, the Math.ceil() method will round up the added “number” and return the double-type decimal value.

Example

Let’s see an example to round up the decimal number using the “Math.ceil()” method:

float number = 9.02f;

Math.ceil() method will round up the value “9.02” to “10”. As we discussed, the ceil() method returns the number into its nearest integer:

System.out.println("Roundup 9.02 by using ceil method:" + Math.ceil(number));

Output

Let’s head towards the next method!

How to Round Up in Java Using Math.round() Method?

The Java Math class has one more method named “round()” that is also utilized to round up the mathematical values towards their closest integer. This method returns the “integer” type value.

To round-up, the “Math.round()” method checks the first decimal value. If it is in between “0-4”, it will return the integer value. If it is in the “5-9” range, the Math.round() method will round up the decimal value to the integer value.

Syntax

The syntax of the Math.round() method is:

Math.round(number)

Have a look at the provided example to learn more about the usage of the Math.round() method.

Example 1

In this example, we have created a variable named “number” having “9.02” as its value:

float number = 9.02f;

Math.round() method will round up the specified variable value to “9” because it is the closest integer of “9.02”:

System.out.println("Roundup 9.02 by using round method:" + Math.round(number));

Output

Example 2

Here, we have a decimal “number” with the value “6.72”, which we want to round up using the Math.round() method:

float number = 6.72f;

Math.round() method will print integer value “7” because 7 is the closest integer of “6.72”:

System.out.println("Roundup 6.72 by using round method:" + Math.round(number));

Output

We have compiled all the basic instructions on how to round up in Java.

Conclusion

To round up in Java, you can use Math.ceil() and Math.round() methods. Math.ceil() method returns double type decimal value while Math.round() returns integer type value. Both of these methods are mainly used to make long, problematic numbers easier for better understanding and calculating. This article discussed the methods to round up the decimal values in Java with detailed examples.

About the author

Farah Batool

I completed my master's degree in computer science. I am an academic researcher and love to learn and write about new technologies. I am passionate about writing and sharing my experience with the world.