Compound Interest Calculator
Growth with any compounding frequency, plus regular additions.
Enter the amount, rate, period and frequency. Add a regular contribution to see the effect of paying in as you go.
Frequency changes the answer
The same nominal rate compounded monthly beats the same rate compounded yearly. That is why the effective annual rate, not the nominal rate, is the honest comparison between two products.
Contributions do the heavy lifting
Over long periods, what you add regularly usually matters more than the rate you earn. Doubling the contribution beats chasing two extra percentage points, and carries no extra risk.
Tax and inflation
Both are outside this calculation. Interest on deposits is taxable at slab rates, and inflation erodes what the maturity value buys. A 7% return during 6% inflation is a 1% real return before tax.
Frequently asked questions
What is the formula?
A = P(1 + r/n)^(nt), where n is the number of compounding periods a year and t the number of years.
Which compounding frequency is best for a saver?
The most frequent, at the same nominal rate. For a borrower, the opposite.