How to write a C Program to Calculate Compound Interest with an example. Before we get into the example, let me show you the formula behind the Compound Interest calculation:

Future Compound Interest = Principal Amount * ( 1 + Rate of Interest ) power Number of years)

Above Code is called Future Compound Interest. Because it contains both the Principal Amount and Compound Interest. To calculate the Compound Interest in C, use below formula:

Compound Interest = Future Compound Interest – Principal Amount

## C Program to Calculate Compound Interest

This C program allows the user to enter the Principal Amount, Rate of Interest, and the Number of years. By using those values, this program calculates compound Interest using the above-specified formula.

/* C Program to Calculate Compound Interest */ #include<stdio.h> #include <math.h> int main() { float PAmount, ROI, Time_Period, CIFuture, CI; printf("\nPlease enter the Principal Amount : \n"); scanf("%f", &PAmount); printf("Please Enter Rate Of Interest : \n"); scanf("%f", &ROI); printf("Please Enter the Time Period in Years : \n"); scanf("%f", &Time_Period); CIFuture = PAmount * (pow(( 1 + ROI/100), Time_Period)); CI = CIFuture - PAmount; printf("\nFuture Compound Interest for Principal Amount %.2f is = %.2f", PAmount, CIFuture); printf("\nCompound Interest for Principal Amount %.2f is = %.2f", PAmount, CI); return 0; }

**OUTPUT**