Java – Display double in 2 decimal places

In Java, there are few ways to display double in 2 decimal places.

Possible Duplicate
How to round double / float value to 2 decimal places

1. DecimalFormat(“0.00”)

We can use DecimalFormat("0.00") to ensure the number is round to 2 decimal places.

DecimalExample.java

package com.favtuts.classic;

import java.math.RoundingMode;
import java.text.DecimalFormat;

public class DecimalExample {

    private static final DecimalFormat df = new DecimalFormat("0.00");
    
    public static void main(String[] args) {
        roundDecimalWithDecimalFormat();
    }

    static void roundDecimalWithDecimalFormat() {

        double input = 3.14159265359;

        System.out.println("double : " + input);
        System.out.println("double : " + df.format(input));    //3.14

        // DecimalFormat, default is RoundingMode.HALF_EVEN
        df.setRoundingMode(RoundingMode.DOWN);
        System.out.println("\ndouble (RoundingMode.DOWN) : " + df.format(input));  //3.14

        df.setRoundingMode(RoundingMode.UP);
        System.out.println("double (RoundingMode.UP)  : " + df.format(input));    //3.15
    }
}

Output

double : 3.14159265359
double : 3.14

double (RoundingMode.DOWN) : 3.14
double (RoundingMode.UP)  : 3.15

Note

You may interest at this article – DecimalFormat(“#.##”) or DecimalFormat(“0.00”)

2. String.format(“%.2f”)

We also can use String formater %2f to round the double to 2 decimal places. However, we can’t configure the rounding mode in String.format, always rounding half-up.

StringFormatExample.java

package com.favtuts.classic;

import java.math.RoundingMode;
import java.text.DecimalFormat;

public class DecimalExample {

    private static final DecimalFormat df = new DecimalFormat("0.00");

    public static void main(String[] args) {
        roundDecimalWithStringFormat();
    }

    static void roundDecimalWithStringFormat() {

        double input = 3.14159265359;
        System.out.println("double : " + input);
        System.out.println("double : " + String.format("%.2f", input));
        System.out.format("double : %.2f", input);

    }

}

Output

double : 3.14159265359
double : 3.14
double : 3.14

3. BigDecimal

BigDecimalExample.java

package com.favtuts.classic;

import java.math.BigDecimal;
import java.math.RoundingMode;

public class DecimalExample {

    public static void main(String[] args) {
        roundDecimalWithBigDecimal();
    }

    static void roundDecimalWithBigDecimal() {
        double input = 3.14159265359;
        System.out.println("double : " + input);

        BigDecimal bd = new BigDecimal(input).setScale(2, RoundingMode.HALF_UP);
        double newInput = bd.doubleValue();

        System.out.println("double : " + newInput);
    }
}

Output

double : 3.14159265359
double : 3.14

Download Source Code

$ git clone https://github.com/favtuts/java-core-tutorials-examples

$ cd java-basic/classic

References

• RoundingMode JavaDoc 11
• BigDecimal JavaDoc 11
• How to calculate monetary values in Java
• Java String Format Examples
• How to round double / float value to 2 decimal places