Compound Interest Calculator
See exactly how your money grows with compound interest. Supports lump-sum investments, monthly contributions, multiple compounding frequencies, and a year-by-year breakdown.
Investment Details
Common: 7–8% FD · 7.1% PPF · 12–14% equity mutual funds
Add a monthly SIP amount to see the combined effect
Results
Fill in the details and click Calculate
See your wealth grow year by year
Free Compound Interest Calculator — See Exactly How Your Money Grows
Compound interest is the single most powerful force in long-term wealth building. Unlike simple interest, which is calculated only on the principal, compound interest earns returns on your returns — meaning every rupee of interest you earn today starts generating its own interest tomorrow. Over decades, this creates an exponential curve that dramatically outpaces inflation and straightforward saving.
Our free compound interest calculator handles both lump-sum investments and regular monthly contributions simultaneously. Whether you are planning a fixed deposit, estimating returns from an equity mutual fund, modelling a PPF corpus, or projecting how long until you reach a financial goal, this tool gives you an instant, accurate answer — no spreadsheet required. Choose from five compounding frequencies (annual, semi-annual, quarterly, monthly, or daily), add a monthly SIP top-up, and get a complete year-by-year breakdown of how your corpus grows.
The formula behind the calculator is A = P(1 + r/n)^(nt), where P is your principal, r is the annual rate as a decimal, n is the compounding frequency per year, and t is the time in years. Monthly contributions are calculated using the future value of an annuity formula and added to the principal growth. Everything runs 100% in your browser — no server, no sign-up, no data shared.
How to Use This Calculator
- 1
Enter your initial investment
This is the lump sum you are starting with — for example, ₹1,00,000 from a matured policy, a gift, or savings. You can start from as little as ₹1.
- 2
Set the annual interest rate
Use the expected or declared annual rate. For FDs, check your bank's current rate. For equity funds, a historical long-term average of 12–14% is commonly used for projections. For PPF, the current rate is 7.1%.
- 3
Choose your time horizon in years
The number of years you plan to keep the money invested. The longer the horizon, the more dramatic the compounding effect. Try 10 vs 30 years to feel the difference.
- 4
Select compounding frequency
Banks and mutual funds typically compound monthly. PPF compounds annually. More frequent compounding gives slightly higher returns. Monthly is the most common choice for most Indian investment products.
- 5
Add a monthly contribution (optional)
If you plan to invest a fixed amount every month on top of the lump sum — like a monthly SIP — enter it here. This can often double or triple your final corpus compared to a lump sum alone.
- 6
Click Calculate
Instantly see your final corpus, interest earned, growth multiple, Rule of 72 doubling estimate, and a complete year-by-year table. Copy the results or share the page with a colleague or financial advisor.
Features
Five Compounding Frequencies
Annual, semi-annual, quarterly, monthly, and daily — covers every investment product from PPF to daily compounding savings accounts.
Lump Sum + Monthly SIP
Model a one-time investment alongside monthly contributions to see the true power of consistent saving.
Year-by-Year Breakdown
A full table showing your total invested, interest earned, and portfolio value at the end of every single year.
Rule of 72 Indicator
See at a glance how many years it takes to double your money at the entered rate.
Visual Principal vs Interest Bar
Instantly see what percentage of your final corpus is money you put in versus money the market gave you.
Copy Results to Clipboard
Copy a formatted text summary with one click — paste it into an email, WhatsApp, or a notes app.
Input Validation
Clear error messages if you enter an invalid rate or time period — no silent wrong answers.
Free, No Sign-Up, No Ads Blocking the Tool
Works on any device, browser, or screen size. Completely free with no subscription or account required.
The Compound Interest Formula Explained
| Variable | Meaning | Example |
|---|---|---|
| A | Final amount (corpus) | ₹3,10,585 |
| P | Principal (initial investment) | ₹1,00,000 |
| r | Annual interest rate (decimal) | 0.12 (12%) |
| n | Compounding periods per year | 12 (monthly) |
| t | Time in years | 10 |
When you add monthly contributions (PMT), the future value of those contributions is calculated as FV = PMT × (((1 + r/n)^(n×t) − 1) / (r/n)) and added to the principal growth. This is the standard future value of an ordinary annuity formula, used in finance and accounting worldwide. The total corpus = principal growth + contribution growth.
Who Uses This Calculator
Fixed Deposit Planning
Compare returns across different tenures and banks before locking in an FD. See exactly what you will receive at maturity.
Mutual Fund Projections
Estimate a potential corpus for equity or hybrid funds using a 10–14% assumed CAGR over 5, 10, or 20 years.
PPF & Government Schemes
Model your PPF corpus at 7.1% (annual compounding) over 15 years, with or without the maximum ₹1.5 lakh/year contribution.
Retirement Planning
Project how much a monthly SIP from age 30 to 60 can grow — and whether your planned savings rate will meet your retirement target.
Child Education / Marriage Corpus
Set a target amount needed 15–18 years from now, then back-calculate how much to invest monthly to reach it.
Business & Finance Students
Verify textbook examples, build intuition for how compounding frequency affects returns, and explore the Rule of 72 in practice.
Frequently Asked Questions
🚀Share this tool with friends!
Help others discover this free tool. Share on your favorite platform!
💡 Did you know? QuickToolkit is 100% free, with no ads or signup required!