How to Format Numbers in Millions in Java

How can I format a number in millions using Java?

DecimalFormat decimalFormat = new DecimalFormat("#,##0.00M");
String formattedNumber = decimalFormat.format(number / 1_000_000.0);

Formatting numbers in millions in Java can significantly enhance the readability of financial or statistical data. Using the right formatting techniques, you can display large numbers in a more understandable format, which is especially useful in applications that deal with significant amounts of data.

import java.text.DecimalFormat;

public class NumberFormatter {
    public static void main(String[] args) {
        double number = 12345678.90;
        DecimalFormat decimalFormat = new DecimalFormat("#,##0.00M");
        String formattedNumber = decimalFormat.format(number / 1_000_000);
        System.out.println("Formatted number: " + formattedNumber);
    }
}

Causes

• Using basic print statements can lead to unreadable large numbers.
• Formatting is necessary for user interfaces displaying sums or statistics.

Solutions

• Utilize Java's `DecimalFormat` class to format the number for display.
• Divide the number by 1,000,000 before formatting to represent it in millions.

Mistake: Forgetting to divide the number by 1,000,000 before formatting.

Solution: Always divide the number by 1,000,000 to convert it into millions before applying the formatter.

Mistake: Using incorrect patterns in `DecimalFormat` which may lead to unexpected results.

Solution: Ensure your `DecimalFormat` pattern matches the desired output, e.g., using `'M'` for millions.