Compound Interest in Java

Calculate compound interest using principal, rate, time, and compounding frequency.

IntermediateModule 1: Basic Java ProgramsExample 13 of 20
compound-interest.java
1import java.util.Scanner;
2
3public class Main {
4 public static void main(String[] args) {
5 Scanner sc = new Scanner(System.in);
6
7 System.out.print("Enter principal: ");
8 double p = sc.nextDouble();
9 System.out.print("Enter annual rate of interest: ");
10 double r = sc.nextDouble();
11 System.out.print("Enter time (in years): ");
12 double t = sc.nextDouble();
13 System.out.print("Enter number of times interest applied per year: ");
14 int n = sc.nextInt();
15
16 double amount = p * Math.pow(1 + (r / (100 * n)), n * t);
17 double ci = amount - p;
18
19 System.out.println("Compound Amount = " + amount);
20 System.out.println("Compound Interest = " + ci);
21
22 sc.close();
23 }
24}

Output

Enter principal: 1000
Enter annual rate of interest: 5
Enter time (in years): 2
Enter number of times interest applied per year: 1
Compound Amount = 1102.5
Compound Interest = 102.5

What's going on

We use the standard compound interest formula:

A = P (1 + r/(100n))^(nt) and CI = A - P.