About the Compound Interest Calculator
What is the Compound Interest Calculator?
Compound interest is interest earned on both the principal and the interest already added to it. Over long periods this “interest on interest” makes money grow exponentially — the reason starting early matters so much in saving and investing.
Enter the principal, the annual rate, the time in years and the compounding frequency. The calculator returns the maturity value, the compound interest earned and the total percentage return, plus a year-by-year growth chart.
How to use the Compound Interest Calculator
- Deposit Amount (₹) (sample: 5,00,000)
- Interest Rate (% per year) (sample: 7.2)
- Tenure (Years) (sample: 5)
- Compounding (sample: Quarterly)
- Press Calculate Compound Interest (results also refresh as you type). The result card shows the Maturity Value, along with Principal, Compound Interest Earned and Total Return on Principal.
Formula used
A = P × (1 + r ÷ n)^(n × t)
- A = the final amount
- P = the principal
- r = the annual interest rate (as a decimal)
- n = the number of compounding periods per year
- t = the time in years
Compound interest = A − P. The more often interest compounds, the higher the effective annual rate: 12% compounded monthly is 12.68% a year.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Deposit Amount (₹) | 5,00,000 |
| Interest Rate (% per year) | 7.2 |
| Tenure (Years) | 5 |
| Compounding | Quarterly |
| Result | Value |
|---|---|
| Maturity Value | ₹7,14,374 |
| Principal | ₹5,00,000 |
| Compound Interest Earned | ₹2,14,374 |
| Total Return on Principal | 42.87% |
Tips for using the Compound Interest Calculator
- Doubling time ≈ 72 ÷ rate (Rule of 72): at 8% money doubles in about 9 years.
- Compare products by their effective annual yield, not the nominal rate.
- On loans, compounding works against you — pay credit-card balances in full.