What is a Compound Interest Calculator?
A compound interest calculator is a free online tool that helps you estimate how your money grows over time when you earn "interest on interest." Unlike simple interest (which calculates returns only on the principal amount), compound interest boosts your savings faster because it adds earned interest back into your investment.
Advanced Compound Interest Calculator
Calculate your investment growth with precision
Investment Growth Results
Investment Summary
| Principal Amount | ₹0 |
| Annual Interest Rate | 0% |
| Compounding Frequency | Monthly |
| Start Date | - |
| End Date | - |
| Investment Duration | 0 years |
| Monthly Contribution | ₹0 |
Year-by-Year Growth
| Year | Start Balance | Contributions | Interest | End Balance |
|---|
Who Should Use This Compound interest Calculator?
Investors
Planning long-term goals (FDs, mutual funds, retirement)
Students
Learning financial growth concepts
Borrowers
Understanding loan interest costs
Savers
Tracking how small deposits grow over time
How to Use Our Compound Interest Calculator
Enter Principal Amount
Input your initial investment amount (e.g., ₹100,000) in the first field.
Set Interest Rate
Enter the expected annual return rate (e.g., 12% for bank FDs).
Choose Duration
Select your investment period using the date picker or manual entry.
Compounding Frequency
Select how often interest compounds (monthly, quarterly, half-yearly, yearly).
Monthly Contributions
(Optional) Add regular deposits to see their impact on growth.
Calculate Growth
Click the button to see your detailed investment projection.
Export Report
Download results as Excel for future reference or comparison.
Key Benefits of Compound Interest
- Wealth Multiplier Effect – Small investments grow significantly over time
- Beat Inflation – Higher returns than regular savings accounts
- Flexible Calculations – Works for FDs, mutual funds, PPF, and loans
- Educational Tool – Great for students learning finance basics
Frequently Asked Questions
Our calculator provides mathematically precise results based on the inputs you provide. It uses standard compound interest formulas and accounts for different compounding frequencies. However, actual investment returns may vary due to factors like changing interest rates, fees, or taxes that aren't accounted for in this simple projection.
Yes, you can use it to understand how debt grows with compound interest. Enter your principal as the loan amount and the interest rate your lender charges. Remember that most loans compound daily or monthly, so select the appropriate frequency.
The more frequently interest compounds, the faster your money grows. Monthly compounding yields better returns than yearly compounding at the same rate because you earn "interest on interest" more often. For example, ₹10,000 at 5% compounded monthly grows to ₹16,470 in 10 years vs. ₹16,289 when compounded yearly.
For more realistic projections, subtract expected inflation from your interest rate. If you expect 2% inflation and 7% returns, use 5% as your rate. This shows your "real" (inflation-adjusted) growth.
APR (Annual Percentage Rate) doesn't account for compounding, while APY (Annual Percentage Yield) does. Our calculator effectively shows APY. For example, 5% APR compounded monthly equals 5.12% APY.
Yes! Simply set your exact start and end dates. The calculator automatically computes fractional years. For example, 1 year and 3 months would be calculated as 1.25 years.
Taxes reduce your effective returns. For taxable accounts, multiply your interest rate by (1 - your tax rate). For example, if you're in the 30% tax bracket with a 6% return, use 6% × 0.7 = 4.2% as your rate.
The CSV export uses the raw date format (YYYY-MM-DD) for better spreadsheet compatibility. Your original dates are preserved in the "Investment Summary" section of the report.