Compound Interest Calculator
This compound interest calculator shows how a single investment grows when its earnings start earning their own returns. Enter your starting amount, the annual rate, the number of years, and how often interest compounds — and watch the future value respond instantly. Compounding is the engine behind every savings account, fixed deposit, bond and long-term investment; this page lets you see exactly how powerful it is with your own numbers.
The lump sum you start with — savings, a deposit, or an investment you have already made.
The yearly growth rate. Savings accounts pay 3–6%; long-run stock-market returns have averaged 8–12%; Indian FDs pay 6–7.5%.
How long the money stays invested. Compounding needs time — the last years do most of the work.
How often interest is added: 1 = yearly, 4 = quarterly, 12 = monthly, 365 = daily. More frequent compounding earns slightly more.
Future value
सेव करने के लिए लॉग इन करें₹4,92,680
What your money grows to by the end — e.g. ₹1,00,000 at 8% monthly-compounded for 20 years becomes ₹4,92,680.
The growth compounding added on top of what you put in — money you didn't have to work for.
Your original stake, shown so you can compare it directly against the future value and interest earned.
How many times over your money grew — a multiple of 4.9 means every ₹1 became ₹4.90.
Frequently asked questions
How do I calculate compound interest?+
Use A = P(1 + r/n)^(nt): principal times (1 + rate per period) to the power of total periods. For ₹1,00,000 at 8% monthly for 20 years that is 1,00,000 × (1 + 0.08/12)^240 ≈ ₹4,92,680 — or just use the calculator above.
What is the Rule of 72?+
Divide 72 by your annual rate to estimate doubling time. At 8%, money doubles every ~9 years; at 6%, every 12; at 12%, every 6. It is a mental-math shortcut for the compound interest formula and remarkably accurate between 4% and 15%.
Is daily compounding much better than yearly?+
Slightly, not dramatically. At 8%, daily compounding earns about 0.33% more per year than yearly — roughly ₹330 extra per year on ₹1,00,000. The rate and the time horizon matter far more than the frequency.
What is the difference between simple and compound interest?+
Simple interest is paid only on the original principal; compound interest is paid on principal plus accumulated interest. ₹1,00,000 at 8% for 20 years earns ₹1,60,000 simple but ₹3,92,680 compounded — compounding adds 145% more.
Does this calculator account for inflation or tax?+
It shows nominal growth. To approximate real growth, enter your expected return minus inflation (e.g. 8% − 3% = 5%). For tax, use your after-tax rate — or hold the investment in a tax-sheltered instrument (PPF, ELSS, EPF) where the headline rate is what you keep.
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