Convert miles to km

In this article, we will take a look at miles to km conversion with java program that takes number of miles to be converted as user input.

miles to km formula
The relation between miles and km is

which means that there are 1.60934 km in a mile.

So, to convert miles to km , we need to multiply the number of miles to be converted to kilometers by 1.60934.
Java program
Below is a java program that reads the number of miles to convert to kilometers as user input using scanner class.
Then, it multiplies this value by 1.60934.

Finally, it formats the result to 4 decimal places.

Scanner scanner = new Scanner(System.in);
System.out.println("Enter distance in miles");
// read miles input
String mileDist = scanner.nextLine();
// convert miles to km
double kmDist = Double.parseDouble(mileDist) * 1.60934;
NumberFormat format = new DecimalFormat("#.####");
System.out.println(mileDist + " miles to km is " + 
                   format.format(kmDist));
scanner.close();

Output is

Above program converts 5 miles to km.

Note that nextLine() reads user input as a string. So, we need to convert it to a double value using Double.parseDouble().

We can also use nextDouble() method of scanner to directly read a double value as shown below

Scanner scanner = new Scanner(System.in); 
System.out.println("Enter distance in miles"); 
// read miles input 
double mileDist = scanner.nextDouble(); 
// convert miles to km
double kmDist = mileDist * 1.60934; 
NumberFormat format = new DecimalFormat("#.####"); 
System.out.println(mileDist + " miles to km is " + 
                   format.format(kmDist)); 
scanner.close();

Output is

It successfully converts 10 miles to km.