Calculate compound interest, total interest earned, and maturity value using your principal, annual interest rate, investment duration, and compounding frequency.
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Calculate how your investment grows when interest is added back to the principal over time.
Currency affects display only — no exchange-rate conversion is applied.
Note: Estimates only, based on standard interest formulas. Actual financial products may differ due to product terms, taxes, fees, or calculation methods. Confirm exact figures with your financial institution.
Calculate compound interest, total interest earned, and future value from an initial investment. Enter the principal amount, annual interest rate, investment period, and compounding frequency to see how the amount may grow over time.
Compound interest is particularly useful for understanding long-term growth because previously earned interest can become part of the amount used to calculate future interest.
Calculate interest using the selected compounding assumptions.
Estimate how an initial amount may grow over the selected period.
Model different compounding frequencies when supported by the calculator.
Separate the estimated interest from the original principal.
Understand how compounding changes projected growth over time.
Use the tool across mobile, tablet, and desktop devices.
Enter the initial principal amount.
Enter the annual interest rate.
Enter the investment period.
Choose the compounding frequency.
Review the final value and total interest.
The standard compound-interest future-value formula is:
A = P(1 + r/n)^(nt)
Interest earned can be calculated as A − P when the formula models the full accumulated value.
Consider ₹1,00,000 invested at 8% per year for five years with quarterly compounding. Using the standard compound-interest formula, the estimated future value is approximately ₹1,48,859.
Interest is calculated on the principal together with previously accumulated interest.
Interest is calculated only on the original principal under the standard simple-interest model.
Compound-interest calculations assume a particular rate, compounding schedule, and time period. Actual investments may have changing rates, fees, taxes, deposits, withdrawals, or other conditions. The result should therefore be treated as a mathematical estimate rather than a guaranteed investment return.
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Compound interest is interest calculated on the original principal plus previously accumulated interest. This means earlier interest can itself contribute to later growth.
A common compound-interest formula is A = P(1 + r/n)^(nt), where P is principal, r is the annual interest rate as a decimal, n is the number of compounding periods per year, and t is the time in years.
Simple interest is calculated only on the original principal, while compound interest includes previously accumulated interest in subsequent calculations.
It can. Because accumulated interest becomes part of the amount used for future calculations, the effect of compounding can become more significant over longer periods.
Yes. With the same nominal rate and other assumptions, more frequent compounding generally produces a higher calculated future value.
A higher rate generally increases the calculated future value when the principal, tenure, and compounding assumptions remain unchanged.
A longer period gives the principal and accumulated interest more time to grow, which can significantly affect the final value under compound growth.
Yes, if monthly compounding is selected. The annual rate and compounding frequency should match the assumptions you want to model.
Yes. Compound-interest mathematics is commonly used to model many deposit and investment scenarios, including fixed deposits. Actual financial products may use their own calculation conventions.
A standard lump-sum compound-interest formula assumes an initial principal. Regular contributions require a periodic-contribution or future-value calculation instead.
The Rule of 72 is a rough mental-math approximation for estimating how long it may take an amount to double at a given annual growth rate. It is an approximation and not a replacement for an exact calculation.
No. A mathematical compound-growth calculation is only an estimate based on the assumed rate. Actual investment returns can vary depending on the financial product.
Yes. The calculator is free to use and does not require registration.
The calculator is designed for browser-based use. Where calculations are performed locally, the values entered are processed on the device rather than requiring an external calculation server.
Results are mathematical estimates based on the assumptions entered. Actual investment returns may differ. Do not interpret projected compound growth as a guaranteed return or financial advice.