Interest is compensation for borrowed money for the period of time. The simple interest is interest on the original principal amount (amount originally received or paid) irrespective of the number of time periods that have passed or the amount of interest that has been paid or accrued in the past.

This online calculator is used for calculating the simple interest, principal amount, rate and time with respect to one another.

1. The value of unknown should be entered as 'X' in the calculator.

2. This calculator can be used for fining compound interest being calculated yearly not monthly or daily.

 Months  Years
 1  $\frac {1}{12} = 0.08$
 2  $\frac {2}{12} = 0.17$
 3  $\frac {3}{12} = 0.25$
 4  $\frac {4}{12} = 0.33$
 5  $\frac {5}{12} = 0.42$
 6  $\frac {6}{12} = 0.50$
 7  $\frac {7}{12} = 0.58$
 8  $\frac {8}{12} = 0.67$
 9  $\frac {9}{12} = 0.75$
 10  $\frac {10}{12} = 0.83$
 11  $\frac {11}{12} = 0.92$
 12  $\frac {12}{12} = 1$
The general formula for Simple Interest is given below.

Simple Interest (I) = $\frac { P \times T \times R}{100}$

Principal (P) = $\frac {100 \times I}{R \times T}$

Rate (R) = $\frac {100 \times I}{P \times T}$

Time (T) = $\frac {100 \times I}{P \times R}$ 

Where $P$ is Principal, $R$ is Rate of interest, $T$ is Time and $I$ is Simple Interest.