# Compound Interest Calculator: Yearly, Quarterly, Monthly > Compound interest calculator: enter principal, rate, years and compounding frequency for the final amount, interest earned and the gap vs simple interest. Source: https://trykosh.com/tools/compound-interest-calculator Free tool - Investing # Compound interest calculator Work out compound interest on any amount, compounded yearly, half-yearly, quarterly, monthly or daily, and see how much of it is interest on interest. Rules checked 25 October 2026Free - no sign-upRuns in your browser Amount after compounding INR 2,20,804 INR 1,20,804 interest, compounded quarterly Compound interest**INR 1,20,804** Simple interest instead**INR 80,000** Effective annual rate**8.24%** Principal **INR 1,00,000**Simple interest **INR 80,000**Interest on interest **INR 40,804** Year by year Year Compound Simple Difference Year 1 INR 1,08,243 INR 1,08,000 INR 243 Year 2 INR 1,17,166 INR 1,16,000 INR 1,166 Year 3 INR 1,26,824 INR 1,24,000 INR 2,824 Year 4 INR 1,37,279 INR 1,32,000 INR 5,279 Year 5 INR 1,48,595 INR 1,40,000 INR 8,595 Year 6 INR 1,60,844 INR 1,48,000 INR 12,844 Year 7 INR 1,74,102 INR 1,56,000 INR 18,102 Year 8 INR 1,88,454 INR 1,64,000 INR 24,454 Year 9 INR 2,03,989 INR 1,72,000 INR 31,989 Year 10 INR 2,20,804 INR 1,80,000 INR 40,804 The more often interest is added, the more it earns, but the jump from quarterly to daily is small. The big lever is time. ## Upload your statement and Kosh does this for you. Upload your statements and Kosh tracks every SIP, FD and deposit in one place, and shows how far you are from each goal. [Start free](/signup?via=tool-compound-interest-calculator) ## How the compound interest calculator works With compound interest, each period's interest is added to the balance and earns interest itself in the next period. Over long stretches this snowballs: the interest on interest eventually outgrows the interest on the original amount. Enter the principal, the yearly rate, the number of years and how often interest is compounded. The calculator divides the yearly rate by the number of compounding periods, grows the principal for every period, and shows the result alongside simple interest on the same terms. The effective annual rate tells you what the compounding frequency is worth. 8% compounded quarterly is 8.24% a year in effect; monthly, 8.30%; daily, 8.33%. Bank FDs compound quarterly; many loans compute interest monthly. The table splits the growth year by year, so you can see the gap between compound and simple interest widen over time. A = P x (1 + r / n)^(n x t) P principal r yearly rate as a decimal n compounding periods a year t years ## Worked example: INR 2.5 lakh left alone for 15 years Rakesh, 40, puts INR 2.5 lakh in an instrument paying 7.5% compounded monthly and forgets about it for 15 years. It grows to about INR 7.67 lakh: INR 5.17 lakh of interest, against INR 2.81 lakh if the interest were simple. Monthly compounding makes 7.5% work like 7.76% a year. Amount after compounding INR 7,67,363 INR 5,17,363 interest, compounded monthly Compound interest**INR 5,17,363** Simple interest instead**INR 2,81,250** Effective annual rate**7.76%** Principal **INR 2,50,000**Simple interest **INR 2,81,250**Interest on interest **INR 2,36,113** The more often interest is added, the more it earns, but the jump from quarterly to daily is small. The big lever is time. [Load this example into the calculator ->](?amount=250000&rate=7.5&years=15&freq=12#calculator) ## Good to know - Compounding works against you on debt too: an unpaid credit card balance compounds monthly at 36% to 42% a year. - Moving from quarterly to monthly compounding adds very little. Time and rate matter far more than frequency. - Compound interest on a deposit is still taxed every year, which reduces how much actually compounds. The real return calculator shows the effect. ## Frequently asked questions What is the formula for compound interest? A = P x (1 + r/n)^(nxt), where P is the principal, r the yearly rate as a decimal, n the number of compounding periods a year and t the years. Compound interest is A minus P. What is the difference between simple and compound interest? Simple interest is earned only on the original principal, so it grows by the same amount each year. Compound interest is earned on the principal plus past interest, so it grows faster every year. How much will INR 1 lakh become in 10 years with compound interest? At 8% compounded yearly, about INR 2.16 lakh. Compounded quarterly, about INR 2.21 lakh. At 12% yearly, about INR 3.11 lakh. Which compounding frequency is best? For savings, more frequent compounding is better, but only slightly. When comparing products, use the effective annual rate, which puts different frequencies on the same footing. ## Sources and assumptions - [Reserve Bank of India](https://www.rbi.org.in/) Rules and rates last checked on 25 October 2026. Results are estimates for planning and education, not tax, legal or investment advice. Kosh is an educational financial planning tool by Primedepth Labs. It is not a SEBI-registered investment adviser and does not offer personalised investment advice, hold your money or execute trades. Markets carry risk; read scheme documents carefully and consult a registered adviser before acting.