Compound Interest Calculator
Calculate compound interest and watch your money grow.
Add money every month (SIP style)
Total Value
₹0
after 5 years
Total Interest Earned
₹0
NaN% return
Total Invested
₹0
Interest Rate
8% p.a.
Effective Annual Rate
0.00%
Investment vs Returns
The Power of Compound Interest
Compound interest is calculated using the formula: A = P(1 + r/n)^(nt). Where P is principal, r is annual rate, n is compounding frequency, and t is time in years. More frequent compounding means higher effective returns—monthly compounding yields more than yearly!
Compound Interest Calculator - Watch Your Money Grow
Calculate how your investments grow over time with the power of compound interest. See year-by-year breakdowns and understand the impact of different compounding frequencies on your wealth.
What is Compound Interest?
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest, which is only calculated on the principal, compound interest allows your money to grow exponentially over time. This "interest on interest" effect is what Albert Einstein reportedly called "the eighth wonder of the world."
The compound interest formula is: A = P(1 + r/n)^(nt)
Where:
- A = Final amount
- P = Principal (initial investment)
- r = Annual interest rate (decimal)
- n = Number of times interest compounds per year
- t = Time in years
Why Use Our Compound Interest Calculator?
- Accurate Calculations: Uses precise compound interest formulas with various compounding frequencies
- Monthly Contributions: Add SIP-style monthly investments to see combined growth
- Year-by-Year Breakdown: Track your investment growth each year
- Visual Representation: See the split between your contributions and interest earned
- Multiple Compounding Options: Monthly, quarterly, half-yearly, or yearly
- 100% Free: No sign-ups, no hidden costs
How to Use the Compound Interest Calculator
- Enter Initial Investment: The amount you're starting with
- Add Monthly Contribution (Optional): Regular monthly additions like SIP
- Select Interest Rate: Choose from quick options or enter a custom rate
- Choose Time Period: How many years you plan to invest
- Pick Compounding Frequency: How often interest is calculated
- View Results: See your total returns and yearly breakdown
Compounding Frequency Comparison
The more frequently interest compounds, the more you earn. Here's how ₹1,00,000 at 10% grows in 10 years:
| Compounding Frequency | Final Amount | Total Interest |
|---|---|---|
| Yearly | ₹2,59,374 | ₹1,59,374 |
| Half-Yearly | ₹2,65,330 | ₹1,65,330 |
| Quarterly | ₹2,68,506 | ₹1,68,506 |
| Monthly | ₹2,70,704 | ₹1,70,704 |
The difference of ₹11,330 between yearly and monthly compounding shows why compounding frequency matters!
The Power of Starting Early
Time is your biggest ally with compound interest. Here's how starting early makes a difference:
| Scenario | Investment Period | Monthly SIP | Total Invested | Final Value (12% p.a.) |
|---|---|---|---|---|
| Early Bird | Age 25 to 60 (35 years) | ₹5,000 | ₹21,00,000 | ₹3.24 Crore |
| Late Starter | Age 35 to 60 (25 years) | ₹5,000 | ₹15,00,000 | ₹94.88 Lakh |
| Very Late | Age 45 to 60 (15 years) | ₹5,000 | ₹9,00,000 | ₹25.22 Lakh |
Starting 10 years earlier with the same investment nearly triples your final wealth!
Common Investment Options in India
Here are typical interest rates for various investment options:
| Investment Type | Expected Returns | Risk Level |
|---|---|---|
| Savings Account | 3-4% | Very Low |
| Fixed Deposit | 6-7% | Low |
| PPF (Public Provident Fund) | 7.1% | Very Low |
| NPS (National Pension Scheme) | 8-10% | Low-Medium |
| Mutual Funds (Debt) | 6-8% | Low-Medium |
| Mutual Funds (Equity) | 10-15% | High |
| Stock Market (Direct) | 12-18% | Very High |
Frequently Asked Questions
What's the difference between simple and compound interest?
Simple interest is calculated only on the principal amount. Compound interest is calculated on principal plus accumulated interest. Over time, compound interest grows significantly faster.
Which compounding frequency should I choose?
Most investments in India compound monthly (mutual funds, recurring deposits) or yearly (FDs, PPF). Choose the option that matches your actual investment. When comparing investments, use the same frequency.
How does monthly SIP add to compound interest?
Monthly SIP (Systematic Investment Plan) contributions are added to your principal each month, and they also start earning compound interest. This creates a powerful wealth-building effect known as rupee cost averaging.
Is 8% a realistic return rate?
For equity mutual funds over 10+ years, historical returns in India have been around 10-12% CAGR. For debt instruments like FDs and PPF, 6-7% is more realistic. Always be conservative with estimates.
How is this different from CAGR?
CAGR (Compound Annual Growth Rate) is the smoothed annual return of an investment over time. The compound interest formula calculates absolute growth. They're related but used for different purposes.
Can I use this for loan calculations?
This calculator is designed for investments. For loans, the interest works against you. While the math is similar, loan calculators typically show EMI and include principal repayment.
What's the Rule of 72?
The Rule of 72 is a quick way to estimate how long it takes to double your money. Divide 72 by your interest rate. At 8%, money doubles in approximately 9 years (72 ÷ 8 = 9).
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