Calculate Simple Interest C Program

By | August 7, 2015

C Program To Calculate Simple Interest

Let us learn how to calculate simple interest in C programming language. We have enlisted two different methods to find simple interest and amount associated with it.

The first method calculates simple interest without using function and the second method has a user – defined function to find the Simple Interest. Simple interest is basically a quick and easy calculation of the interest charged on a given principal amount.

Formula To Find Simple Interest

Simple Interest = (p * n * r) / 100


             p = Principal Amount,

             n = Number of Years / Period

             r = Rate of Interest


              Principal Amount = ₹ 3000

              Period = 3 years

              Rate of Interest = 10%

              Simple Interest = ₹ 900

This C program takes the values of p, n and r from the user and then applies the above given mathematical formula for simple interest calculation.

Must Read: C Program To Calculate Compound Interest using Functions

Method 1: C Program To Find Simple Interest without Function

Method 2: C Program To Calculate Simple Interest using Function

Must Read: C Program To Display Current Date and Time


Calculate Simple Interest in C Programming Language with and without Functions

In case you get any compilation errors in this C program to calculate simple interest or you have any doubts about it, let us know about it in the comment section below.

6 thoughts on “Calculate Simple Interest C Program

  1. Monish Sawant

    I will always prefer the Simple Interest using Function code in C Programming since it gives more modularity and resusability to the function.

  2. Vishwajeet Pawar

    I want to print 3 digits after the decimal point in the result. Can you help me with that?


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